Fedora, I usually wait 1-2 weeks for the last bugs to be found+fixed and extensions to catch up, and then just upgrade in-place. Haven’t had a major upgrade problem for years now, it’s mostly as smooth as any other offline update. And I don’t feel like I have to reinstall the OS every few years on Linux either.
Welcome to the Linux community. :)
You will probably never understand everything about Linux and all of its included and associated systems. That’s completely fine, no one does! That’s why we are many, and it’s what asking for advice or help is for. You can just learn whatever interests you at your own pace, and know that there will always be interesting things you haven’t seen yet.