Buy an inexpensive NUC6 and use it as an inexpensive learning platform. I keep a stack of small SSD hard drives on-hand and when I want to try something risky, I pop in a different hard drive, one I don’t care about it if I screw up the OS with. The worst that happens is that I have to wipe the OS and start over. It’s like a game. When you fatally damage the OS, it’s like you’ve run out of lives (in a game) and have to start over again at the bottom level. After you’ve mastered doing what you need to know, you pop in your good hard drive (the one you don’t want to mess up) and make your changes, doing it correctly the first time. Fear of damaging your OS or files in an irreversible way is a valid fear, and can prevent you from learning. Your problem probably isn’t barriers to learning what you need to learn. But you need a safe learning place.