get the Sapphire and give it to the men at the Pokemon center in island 1
Capture all the Pokemon in Kanto then National then get all the pokwmon in your PC and get some to Lv100.Yours Truly- yehthatisme
its in 5 island
Team rocket will go to the dotted hole after five island in leafgreen, but I'm not sure about firered.
you get to trade with Sapphire
Sludge bomb: team rocket HQ (island 5)
In the lower eastern part of the island, just follow the grass trail, and you will see a small warehouse
You find the sludge bomb, team rocket HQ on island 5.
It is south of the Pokemon center on island 5. If there is a scientist blocking the way go to icefall cave in island 4 and beat team rocket.
bring the Sapphire back to one island and give it to that one guy in the Pokemon center and then go and fight mewtwo in cerulean cave
The first code is given by a rocket grunt in mt ember after getting the national dex, the second code is given by a scientist who steals the sapphire from you in dotted hole.
The Team Rocket warehouse is in the Goldenrod Tunnel, but you have to get the key first which is obtained from a Team Rocket member in the 5th Floor of the Radio Tower.The same way in Soul Silver: after you get the seventh badge, Team Rocket will have taken over the Radio Tower in Goldenrod City. Team Rocket is defeated when you rescue the Director and beat all four Rocket Executives.
By this point you will have both the passwords required for the Rocket Base on Island 5. Head to Island 5 and go through the Rocket Base, the Scientist is there.