I’m the kind of guy that enjoys reading the user manuals and getting everything out of a “thing.” Where can I find that?

I’m a new OLED SD user (never owned one before), and I’m new to Linux, and pc gaming as a whole. So the simplicity and ease I’m used to isn’t there. I’d like to learn myself up without having to slog through hours of YT vids.

What’s proton? How do I mod games in steam? Can I mod games in steam? What about desktop mode? I understand I can use DT mode like a normal computer but there wasn’t anywhere I found that explained that functionality and how to access it on my SD.

Please help!