* The games are separate: The Pokemon games are typically designed with separate regions. You finish one region (like Johto in Pokemon Gold, Silver, and Crystal) and then, if there's a sequel, you move on to the next region (Kanto in those games). You don't go back to the previous region after defeating the champion there.
* Post-game content: After defeating the champion, most Pokemon games offer post-game content within the same region. This can include:
* Catching remaining Pokemon: Many rare or powerful Pokemon might not be available until after the main story is complete.
* Training and battling: You can train your team and challenge trainers for more experience.
* Side quests: Many games have optional quests or events that become available once the main story is over.
Exceptions:
* Pokemon FireRed and LeafGreen: In these games, you travel to Kanto *before* defeating the champion of Johto. It's part of the main storyline.
* Pokemon Yellow: In this game, you start in Kanto and don't visit Johto at all.
Possible Misunderstanding:
Perhaps you are thinking of Pokemon Let's Go, Pikachu & Eevee. These games take place in Kanto and have a post-game feature where you can battle Red on Mt. Silver, a location from the original Pokemon games. However, it's not about flying to another region; it's about returning to a specific location in the same region.
Let me know if you have any other questions!