Can I get all the way to the champion without having to erase my old data? Like, is there any place where it forces you to save ect?
In Pokemon Black and White the game doesnt Force you to save. Saving is an option. But you save after defeating the Champion. The Gear Station forces you to save. I believe that Game Freak didnt put in Forceful Saves because if something went wrong, and if it saved, there would be no going back. I HIGHLY recommend saving though.
Hope I helped.
Yes, as long as you don't go into the Gear Station.
Note: You kinda save after the champion, no matter what,