Pokémon Red Version, Blue Version, and Yellow Version - Walkthrough - What’s next?
This information might be useful when playing Pokémon FireRed Version and Pokémon LeafGreen Version, too.
What’s next?
After waiting for the credits to roll, press the A button to restart the game. You’ll be sent back to Pallet Town again. The first thing to do now is fly to Cerulean City, go north to Route 21, and surf on the water to the cave known as the Unknown Dungeon.
Next, fly back to Cerulean City and travel through Route 9, and surf on the water near the rock tunnel to reach the Power Plant.
Finally, fly to Fuchsia City Seafoam Islands.
There! You’re done. Spend the rest of your time in the game searching for all the Pokémon