I don't remember well how it was when I started since I was 13.

So I guess by trail and error, reading wikis, wanting to customize and explore the system, finding out how it differed from Windows... Stuff like that, curiosity and the freedom GNU/Linux gave me regarding just about anything on my system definitely helped.

Generally just use it, and you'll stumble upon places like the arch wiki, stackoverflow, ubuntu questions, reddit (ew) and more, hopefully not 4chan but rarely their resources can be handy. Also since the commandline is the universal interface of GNU/Linux you'll definitely stumble upon guides with commands to paste, that'll help you get udjusted to it.

Also definitely try youtube, GNU/Linux content has blown up massively so you won't be stuck with mr. petite bougie innawoods dumbass and /g/ that leads a young mind to have fucked up politics.