If you're curious, ProtonDB is the place to check if the game you're interested in is supported (and how well).

You can also just browse and see what is supported. Here is the list sorted by the highest user ratings: https://www.protondb.com/explore?sort=userScore

Sometimes though a game wont work on a specific system or hardware configuration, even though ProtonDB states it works well. Had such a case recently and tried all the fixes people suggested. Might have been some new patch or so introducing more issues or might have been my hardware setup. No idea.