The last time I fully rebuilt an engine I was 15-16. I have worked on alot on stuff through the years to save money and keep it running like my burb though. When I was replacing ball joints, my retired neighbor mechanic encouraged me when I was ready to give up. You do learn as you go. "Ah maybe do that different next time"
I tend to obsess, worry about getting it wrong or in trouble. Plan go for it, learn.
You tube can be good for a particular project, alot of video on same thing, and alot of diy to show you what NOT to do. Entertaining! We should have a thread for that. "Watch this guy use his professional buddy to do his ac 3x" Anyway, continue to seek help, and you will find.