Joey has a PC running PopOS Linux but he wants to learn more about the secrets of the system. Leo says that there are books, but generally, it's through communities that you learn. REDDIT has many good subreddits. Reddit.com/r/linux is the definitive subreddit for it. Also, the Pop_OS subreddit would be good. Reddit.com/r/pop_os. There are also Linux and PopOS communities on Discord. That would be good too.