You have to beat the Elite Four at least once then talk to Celio (the guy in the Island's Pokemon Center) then go to Mt. Ember and learn the password and battle them.
Chat with our AI personalities
You look for the team rocket boss and before you have face team rocket grunts and also your rival
The rocket team are not on four island. there are two grunts up a ways of Mt. Ember north of one island, however the Rocket Base is on five island. It requires two passwords if you want to enter. Work that bit out for yourself.
there are no team galactic grunts in that game. only team rocket, and they are not at lake of rage.
The first password you will get from 2 team rocket grunts at mt ember (after you get national dex). Second is in dotted hole at island 6 when the man working for team rocket who meets you near the sapphire
first you have to use dig then they will move HOPE THIS HELPS