you just need to right-click on the game (in the left panel), go to Properties -> Compatibility, and set it to Proton Experimental

You can also enable it for all available games from Settings > Compatibility (and you’ll still be able to override the version on a per-game basis as well)

Glad I could help!

(Also, not sure why you’re being downvoted. You made a valid assumption, and not knowing is not a sin. The dismissal of evidence is, which you clearly didn’t do. )

Some windows games running on proton beat native windows performance. So yes.

Here’s a recent benchmark.

Edit: here’s the AMD GPU version if that’s what you’re using: https://youtu.be/D45AknAsIPw