steam is available from the Manjaro repository, as well as steam-native-runtime, steam-deckify and a few other related packages. For Windows games, there is protontricks, as well as a couple of other related packages. 
wine in and of itself is available from the Manjaro repository as well, and it can run lots of native Windows software, but not quite everything. But then again, why would you run Windows software when there’s so much Free & Open Source software that natively does the same things on GNU/Linux?
However, because you’re new, I must draw your attention to the following short essay. 