Full Walkthrough
Pallet Town
Try to walk out of the Town and Prof. Oak will stop you. He'll bring you to his lab and make you decide on what Pokemon you want. The choices are Charmander, Squirtle, and Bulbasaur. Pick one and Gary will pick the Pokemon that has a advantage over you. Bulbasaur will be the best choice. The first battle will be very easy because all you have to do is keep on attacking. Even if you don't beat him you can still move on to the next town.
Path to Veridian City
This is simply a short path with not many wild Pokemon(Note:You can not catch any yet)Talk to the people along the way. One of them will give you a potion.
Veridian City
Now you might want to heal your Pokemon at the Pokecenter if you got hurt. After you have done that, go to the Pokemart and the cashier will give you an item to give to Prof. Oak.
Pallet Town
You might want to heal your Pokemon at your house by talking to your mother. Go to Prof. Oak and give him the item. Gary will then walk in and Prof. Oak will give both of you a Pokedex. A Pokedex will record information of Pokemon you have seen and have captured. Now go to Gary's house to get a Town Map from his sister. The house is to the right of your house.
Veridian City
Now you can buy Pokeballs at the Pokemart. You should buy around 5 Pokeballs. Once you have them you can catch Pokemon, but watch out you might run out. Catch Pokemon from the path leading to Pallet Town and the left of Veridian City.
Left of Veridian City
Here you can catch Spearow, Nidorans(both genders), Rattata, and Pidgey. Go up and you'll have to fight Gary. This should be a real easy battle if you have all your Pokemon on L.7 and 2 Pokemon on L.8.
Above Veridian City
Now the guy that was lying on the ground had his coffee and will let you pass. Go up out of the town and you'll find some bushes to fight Rattata and Pidgey. After the bushes you'll reach a house.
Veridian Forest
This is the forest you can reach by going through the house. Here you can catch Caterpie, Metapod, Weedle, Kakuna, and some Pikachus. Although Pikachus are very rare, it is worth the time. Now you'll have your first battles other than Gary. The Bug Catchers won't be much of a match. If you have a Spearow it will be even easier. You'll earn some money from beating them. Make sure you get the items in the forest.
Out of Veridian Forest
Not much here. There are a group of bushes here. They contain Rattata and Pidgey.
Pewter City
This is the town that has a gym you can go into. You can visit the museum first. It shows some extinct Pokemon. When you fight Brock, make sure you have your Pokemon above L.10 and some on L.15. Brock: L.12 Geodude, L.14 Onix. This battle can be quite hard if you don't have high level Pokemon.
Path to Mt. Moon
On this path you'll fight many Bug Catchers and some girl trainers.
Watch out for poison. On the way you'll find some bushes where you can
catch Spearow, Pidgey, and Rattata. After that a patch of bushes will
contain Jigglypuffs. They are very rare though. At the end you'll find
a Pokecenter and Mt. Moon.
Pokecenter
Here you should heal your Pokemon and use the PC if you wish. Also there is a man who will sell you a Magikarp for 500 yen, but you can catch it later on.
Mt. Moon
This is the first cave of the game and it is also a long one. In here you can catch Zubat, Paras, Geodude and some Clefairies. At the beginning you can go to the right and grab 2 items and fight a trainer.After that go to the right and fight another trainer. Next you'll come to some stairs. Go down if you wish to get an item. There is also a Team Rocket trainer at the end of the path of the stairs. When you have came back up you can go down to grab 2 more items and fight some 2 trainers. I would fight all the trainers since they give you more experience than wild Pokemon. Come back up and follow the path to the right and you'll see 2 more trainers. There'll be another flight of stairs that leads to more items. Now go to the left of the and you'll fight yet another trainer. Once he has lost go into the staris and follow the path to the other section of this cave. In this section you'll have to fight a Team Rocket trainer right away. This battle can be extremely hard if most of your Pokemon are on L.10, since he has a L.16 Raticate. Next follow the path to fight about 3 more trainers. When you reach the trainer that is in front of the fossils, fight him and pick a fossil. The right is the Dome Fossil and the left is the Helix Fossil. The Helix Fossil contains the DNA of Omanyte. The Dome Fossil has the DNA of Kabuto. Give these fossils to the professor on Cinnabar Island later and he'll give you the Pokemon. Now exit Mt. Moon.
Path to Cerulean City
Not much of a path. You can get TM14 here. And the bushes have Ekans, Pidgey, Rattata, and Spearow.
Cerulean City
Here you can trade Pokemon at the Trading Center. Don't worry about the bike. You get it later. Now you must face Misty. She is pretty hard if you don't have Bulbasaur. If you don't you can go above Cerulean City to catch Oddish, but if you do that you'll face Gary and about 9 more trainers. Back to Misty now. Misty: L.18 Staryu, L.21 Starmie. After you have beaten her go above Cerulean City.
Above Cerulean City
Here you will fight around 15 trainers straight and Gary. Not that hard. Just watch your HP and when it goes down, go to the Pokecenter. In the bushes here you can catch Abra, Oddish, Pidgey, Caterpie, Metapod, Weedle, and Kakuna. There also 2 items here. At the end of the road will be a house.
Bill the Pokemaniac
You'll find a Pokemon here. This is actually Bill the Pokemaniac. Follow his instructions to turn him back into a human. He'll give you the S.S. Ticket. Once you have done that check out his PC.
Below Veridian City
To get here you must go into the house above the gym and go through it. Then head down until you reach 3 houses. One is a Daycare Center for Pokemon. Another you can't get into yet and the right one leads to Vermillion City. There is a tunnel inside the house. Go through it. You won't run into wild Pokemon here.
Outside of tunnel
Here you'll have to fight around 5 trainers. You can catch Oddish, Pidgey, and Mankey. Go south into the town.
Vermillion City
Now you can heal your Pokemon. Go to the right of the town. Then go down to the dock. Talk to the guy there and he'll let you aboard the S.S. Anne.
S.S. Anne
In the S.S. Anne you'll have to fight every single trainer. Then go to the captain. Right when you enter the captain's room, Gary will fight you. After that, talk to the captain and he'll give you HM1, Cut. Now use it on a Pokemon. Leave the S.S. Anne and it'll depart.
Vermillion City Gym
Here you'll fight 2 trainers. Then solve a little puzzle. You'll have to search the barrels. Then fight Lt. Surge. Lt. Surge:L.21 Voltorb, L.18 Pikachu, L.24 Raichu. Easy battle. A lot easier than Misty.
House above Vermillion City Gym
In here talk to the guy for a Bike Ticket. He's the one at the top.
Cerulean City
Bring the Bike Ticket to the Bike Shop here. You get the bike here for free since you have the ticket.
Diglett's Cave
This is the cave to the right of the dock of Vermillion City. You can catch Diglett and Dugtrio. Dugtrio is very rare. Walk to the end of this short cave and go out.
Outside of Diglett's Cave
Out here cut down the tree and keep on walking until you reach another house. You can pick up 2 items along the way. Talk to a guy inside the house. He is Prof. Oak's Aid. He'll give you HM5, Flash.
Right of Cerulean City
Cut down the tree here and fight around 10 trainers. You can pick up some items. The bushes here have Ekans, Spearow, Voltorb, and Growlithe. At the end there is a Pokecenter. Heal your Pokemon and prepare for another long cave.
Rock Tunnel
Go in and use Flash. In here you'll find Geodude, Zubat, Onix, and Machop. Now follow the path the path and fight the trainers. Most of the their Pokemon are Rock type. Ocassionally they will use Fighting type. If you have Squirtle or Gyarados(evolve Magikarp), it will be a piece of cake. You'll also pick up some items up along the way.
Outside of Rock Tunnel
Fight these trainers if you have enough HP. Walk south to reach Lavender Town.
Lavender Town
Nothing to do here but to buy items and heal Pokemon. You can also rename your Pokemon at the Nickname Changer's House.
Left of Lavender Town
You fight alot of trainers. The bushes here have Pidgey, Mankey, Ekans, and Growlithe. At the end you'll reach 2 houses. Go in the top one and go into the tunnel. Walk through to reach Celadon City.
Path to Celadon City
Not much here but a patch of bushes. In there you'll find Pidgey, Mankey, Oddish, and Growlithe.
Celadon City
Go heal your Pokemon and fight the Gym Leader, Erica. Erica and her trainers use Plant type Pokemon. Erica:L.29 Victreebel, L.24 Tangela, L.29 Vileplume. After beating her you can go into the Game Corner and talk to the Team Rocket member next to the counter. Fight him and he'll head to the right. Search the thing on the wall and you'll open up a flight of stairs to the right.
Team Rocket Hideout
In here you'll find about 5 items and around 10 trainers. First fight all the trainers and after each battle talk to each of them. One of them will give you an item. You'll also have to solve some puzzles (not to hard, in fact none of the puzzles are hard in this game compared to some others)Now after you have gotten the item that the TR member gives you. Go into the elavator and go to the top floor. Here fight the 2 guards that are by the doorway and the door will open. Now talk to Giovanni, leader of Team Rocket. This isn't difficult. After pick up the item on the ground. This is the Silph Scope.
Pokemon Tower
This tower is at the top right part of Lavender Town. Go in and walk up the stairs. Fight Gary here. Now head up and you'll fight around 13 trainers. Watch out! Every one uses Ghastly or Haunter. This is a pretty hard part of the game. You can catch Ghastly, Haunter, and Cubone here. At the top you'll fight Marowak. After you'll find some TR members. Fight them and talk to the old man. He'll give you the Poke Flute.
Sleeping Snorlax
Now you can either go back to Celadon City and fight the Snorlax there to get Old Amber and Slots or go beat the Snorlax and follow the path.It's your choice. The first 2 sections below are for the Old Amber and the Slots.
Left of Celadon City
Here you'll find some bushes and a Snorlax. In the bushes are Pidgey, Venonat, Oddish, and Gloom. Beat the Snorlax or catch it, since there is only 2. Now go in and talk to the guy upstairs and he'll give you HM2, fly.
Old Amber
Go back to Pewter City and go in the museum by cutting down the tree. Talk to the guy for the Old Amber. When you get to Cinnabar Island to turn Old Amber into Aerodactyl.
Slots
Very simple. Just go into Celadon City and talk to the guy in the corner at the bar. He'll give you Coin Case. Now go to the Game Center and talk to the people. Some of them will give you coins.
Left of the Snorlax
Here you'll need your bike because you'll be riding down hill. Here you'll fight around 20 trainers who also have bikes. You can also catch some Pokemon. They are the ones you have seen before, so don't bother. At the end of this long path you'll find Fushia City.
Below Lavender Town
This is just another route you can take to Fushia City. Beat the Snolax and then head down. Fight more trainers and collect the items.
Fushia City
Here you'll have to fight Koga, the gym leader. He uses poison Pokemon. Koga:(find out later). After that is finished head to Saffron City.
Celadon City Mall
Here you can buy most of the items in the game, but that isn't what you are here for. Go to the top floor. You'll have to take the elevator up to the 5th floor and walk up the stairs. On the wall next to the stairs you will find a vending machine. Buy some Fresh Water, Soda Pop, or Lemonade.
Saffron City
To get here go into one of those houses with the guards that say they are thirsty and give them the water. They'll let you pass. You'll reach Saffron City. Here most of the houses you can not go into yet. Go to the top to find 2 gyms. Go in to the left one. The other gym has a guard in front of it. Beat all the trainers in here and you can choose between 2 Pokemon. They are Hitmonchan and Hitmonlee.
Silph Company
This is the company that made the silph scope. Go in the house at the middle of the city. It's more of a building. Fight through 11 floors of gruesome trainers and sooner or later you'll get the key to the doors. At the end you'll find Gary. Fight him and talk to the guy there. He'll give you a Lapras. Now go into the warp and follow the short path to Giovanni. Beat him and talk to the guy on the sofa type thing. He'll give you a Master Ball!
Saffron City Gym
This is the gym to the right of where you got Hitmonchan and Hitmonlee. Go in and solve the easy puzzle to fight Sabrina. Sabrina:L.38 Kadabra, L.37 Mr. Mime, L.38. Venomoth, L.43 Alakazam. Kind of hard boss, since she uses psychic Pokemon. Before you leave Saffron City, you might want to go into 1 of the houses and talk to the guy. He'll give you a Item Finder if you have 50 or more Pokemon. Next head to the top of Fushia City into the Safari Zone.
Safari Zone
Many items to pick up here. Pick them all up if you can, since you can only walk 500 steps. One of the items contain the Gold Teeth.I think this is the way to the Secret House. I'm not sure. First go to the right. Then when you come to this hill go up. Then come back down on the other side. Then head up and turn left. Then go down till you reach the arrows pointing down. Instead go up and turn right. Then go up and turn left. You'll find the Secret House. Remember to pick up all items. The Safari Zone also contains many different types of Pokemon. Safari Zone Screen 1:Nidoran (Male), Nidorino, Nidoran (Female), Nidorina, Venonat, Rhyhorn, Scyther,Chancey, Parasect, Exeggcute. Safari Zone Screen 2:Nidoran (Male), Nidorino, Nidoran (Female), Paras, Parasect, Kangaskhan, Doduo, Exeggcute, Scyther. Safari Zone Screen 3:Nidoran (Male), Nidorino, Nidoran (Female), Nidorina, Paras, Tauros, Chansey, Venomoth, Rhyhorn, Exeggcute. Safari Zone Screen 4:Nidoran (Male), Nidorino, Nidoran (Female), Exeggcute, Venonat, Venomoth, Kangaskhan, Doduo, Tauros. In the waters you can catch a Dratini and some other Pokemon. You'll have to swim or use a rod.
House Right of Fushia City Gym
Talk to the guy. He'll give you HM4, Strength. Push the rock out of the way there and get the item.
Water Route
This is below Fushia City. Take this route to reach the Seafoam Islands. Fight about 20 trainers along the way. Watch your HP!
Saefoam Islands Cave
Not that long cave. You can catch a lot of water Pokemon and Articuno. The water Pokemon include Krabby, Seel, Dewgong, Zubat, Golbat, Slowpoke, Psyduck, Golduck, Staryu, and Shellder. Push the rocks in the holes and you'll soon find your way...
Water Route to Cinnabar Islands
Here you'll fight around 10 trainers. At the end you'll reach Cinnabar Island.
Laboratory
Go to the house to the left of the Pokecenter and talk to a Prof. If you have the Old Amber, Helix Fossil, or Dome Fossil, he'll give you a Pokemon.
Abandoned Pokemon Factory
Very nutty place, since it is frustrating when you choose the wrong path. Well fight around 5 trainers in here. You can catch Grimer, Muk, Koffing, Wheezing, Ponyta, and Growlithe. At the end pick up the item and be sure talk to everyone.
Cinnabar Island Gym
Easy place fight or talk to computer near wall to open door. If you talk to the computer you'll have to answer a Pokemon question. At the end fight Blaine, the gym leader. Blaine:L.42 Growlithe, L.42 Rapidash, L.40 Ponyta, L.47 Arcanine. Easy if you chose Squirtle or Charmander.
Water Route to Pallet Town
It's back to Pallet Town. Fly to Veridian City or take this path. Fight some trainers and walk to Veridian City.
Veridian City Gym
It's is open now. It has the features of the Team Rocket Hideout. Figure it out and fight... Here's a hint(you fought him twice before)Giovanni:L.42 Dugtrio, L.50 Rhydon, L.45 Nidoking, L.43 Nidoqueen, L.45 Rhyhorn.
Left of Veridian City
A rematch at the beginning of the game. Fight Gary!
Pokemon League
Show the officers your badges. Boulder! Cascade! Thunder! Marsh! Soul! Rainbow! Volcano! Earth! Now enter Victory Road.
Victory Road
Push the rocks into those holes. Here you can catch Zubat, Golbat, Machop, Machoke, Geodude, Graveler, Onix, Moltres, and Marawak. At the end you'll reach Indigo Plateau. Heal and buy many revives, potions, and ethers. Make sure Pokemon are on L.50 and go in.
Elite Four
First there's Lorelei. Ice and water Pokemon. Lorelei:L.? Dewgong, L.? Cloyster, L.? Slowbro, L.? Jynx, L.? Lapras. Then Bruno, rock and ground is his specialty. Bruno:L.? Onix, L.? Hitmonchan, L.? Hitmonlee, L.? Onix, L.? Machamp. Next Agatha, ghost specialist. Agatha:L.? Gengar, L.? Golbat, L.? Haunter, L.? Arbok, L.? Gengar. Last Lance. Lance:L.? Gyrados, L.? Dragonair, L.? Dragonair, L.? Aerodactyl, L.? Dragonite
Pokemon Master
Gary is the champion. Beat him and you'll be a Pokemon Master. Gary:(it depends on what Pokemon he picked at the beginning)Chamander: L.? Pidgeot, L.? Alakazam, L.? Rhydon, L.? Gyrados, L.? Exeggcutor, L.? Charizard. Squirtle: L.? Pidgeot, L.? Alakazam, L.? Rhydon, L.? Arcanine, L.? Exeggcutor, L.? Blastoise. Bulbasaur: L.? Pidgeot, L.? Alakazam, L.? Rhydon, L.? Gyrados, L.? Arcanine, L.? Venusaur. Now you have beaten the entire or game or have you...?
Abandoned Electric Plant
This can be reached once you've gotten the swim ability. Go to the entrance of Rock Tunnel and head up. swim at the shore south to coma to a building and go in. Catch Pikachu, Raichu, Electabuzz, Voltorb, Magnemite, and Magneton. At the end capture or kill Zapdos.
Mewtwo's Cave
This is the cave to the left of Cerulean City. Go in and capture Ditto, Wigglytuff, Chansey, Dodrio, Venemoth, Marowak, Rhydon, Electrode, and Kadabra. At the end fight(and hope you still have the Master Ball) Mewtwo. Capture this L.70 Pokemon!
150 Pokemon Diploma
Get the diploma at Celadon City from some guy