I think you can even boot from an USB flash drive without actually installing the OS, if you ever need to...

I learned a bit by doing more things "by hand" with commands in a terminal rather than using GUI that hides what happen. Maybe it can help you understand a few more things as well.

Some distributions, like Arch, invite you more often to do so than others, like Ubuntu. But after using Arch a few, I felt that it handles most things for the user, that has does not have so many things left to handle on its own.

For Linux distributions like Arch, Crux, Gentoo, Slackware, Alpine, Void... and BSDs; there is only a minimal system installed by default. Not even a graphical user interface. They need to be installed, and this helps to figure out what is essential to run the system, and what you can install on-top of it.