

Do you really need a guide? It works exactly the same as Windows. The only difference is you need to run it through WINE with Proton. That’s easiest handled with Heroic Launcher or Lutris, which you’re probably already using one of these already. Just add the executable and launch it. (You may need to run an installer first, which Heroic at least makes really easy.)
Saying “do you want to play CoD tonight” is different than discussing why the gameplay of CoD is good/new/innovative/whatever.
I actually did see people discuss the campaign of the new CoD (or maybe the one before) because it was actually fairly unique for them. Other than that, the only time I hear about CoD is people talking about how much money it makes, how bad the skins are, or things like that. It holds almost no relevance in game discussion circles because everything they did well has been innovated on since then.
People talked about how smooth and responsive CoD 4 was, because it was innovating. People don’t talk about the mechanics of whatever the latest CoD is, because it’s not doing anything worth copying.