First, borrow at least a half dozen books from a tech library at a votech place.
After you read them there will still be some things you don't know and sometimes these things are pretty important.
We had a tube tester at work that looked like the dashboard of a 747.
I wanted to get the manual for it but some guy said, "What for? It's self-explanatory."
This manual had 65 pages.
I do not know why people say things like that.