In addition to what Wolf told you, here's a few little extra tidbits:
Some games have native Linux versions. If they don't, you typically play them through Proton, a gaming-ready version of the Wine compatibility layer. Steam directly supports this through compatibility settings (Steam -> Settings -> Compatibility for default settings or Game properties -> Compatibility for per-game settings). Sometimes specific Proton versions will be better for specific games but usually you don't need to worry about it much.
Proton is damn good. Expect performance for most games to be within ± 5% of the performance you'd get on Windows. Yes, some games run better on Proton than on native DirectX.
Valve recently decided to enable Proton by default for games that don't have a Linux version. You can enable it yourself in the settings if it isn't enabled yet.
You can even force games with a native Linux version to use Proton by setting it in the game's compatibility settings. In that case Steam will download the Windows version.
I played Arknights for a bit because there's actually a pretty solid tower defense game in there. There's not a big selection of good games for Android and I wanted something I could play when I have no laptop with me.
Unfortunately the good gameplay is buried under tons of attention hogging gacha bullshit.
I stopped playing once I realized that I was spending more time doing chores than actually playing through interesting content. Also, while the BGM is nothing short of lavish, the presentation of the story is like a very cheap VN, which basically killed any hope of getting engaged in the story or the characters.
I didn't spend much more than maybe twenty bucks on it so it's not too bad given the partially solid gameplay. But yeah, I'm done with live service bullshit games.