Steam

Steam runs natively on Linux. You can probably just install it from your App store.

Use Steam (Runtime), not Steam (native). Trust me, this will prevent problems.

Enable Steam Play for all games

In order to run games that are not explicitly whitelisted by Valve, go to Steam -> Settings -> Steam Play and check "Enable Steam Play for all other titles" and then select "Proton Experimental" in the drop down menu.

If something doesn't work, check out Proton-GE.

ProtonUp-Qt

You can use ProtonUp-Qt to make the installation and update process of Proton-GE simple:

• 1. Download the ProtonUp-Qt AppImage
• 2. Mark the AppImage as executable
• 3. Double-click the AppImage to run ProtonUp-Qt