I've always approached learning Linux by just diving into it and bashing my head against problems as they come until I either solve them or give up, the latter being the more common outcome.
I wouldn't take this approach with other pieces of software though - I'd read guides, best practices, have someone recommend me good utility tools or extensions to install, which shortcuts to use or what kind of file hierarchy to use, etc.
For example, for python I'd always recommend the "Automate the boring stuff with Python", I remember learning most Java with that "Head first Java" book back in the days, c# has really good official guides for all concepts, libraries, patterns, etc.
So... lemme try that with Linux then! Are there any good resources, youtube videos, bloggers or any content creators, books that go explain everything important about linux to get it running in an optimal and efficient way that are fun and interesting to read? From things like how the file hierarchy works, what is /etc, how to install new programs with proper permissions, when to use sudo, what is a flatpak and why use it over something else, how to backup your system so you can easily reconstruct your setup in case you need to do an OS refresh, etc? All those things that people take for granted but are actually a huge obstacle course + minefield for beginners?
And more importantly, that it's up to date with actually good advice?
It's no reddit in terms of quantity but honesty I've had higher quality topics and discussions here than there. Lemmy/kbin might not have taken off in the mainstream to offer a variety of subjects but when it comes to tech and software I think it's covered well enough and people are generally nicer about it. The main problem is lack of (remotely) good seach function, I dont think the threads are getting indexed by google and the on-site search is atrocious.
I don't know of any discord programming communities, I wish forums were still a thing but the only live one I know of is the jellyfin one after they moved from reddit. Other than that it's here or the various subreddits