As a self taught guy, if you're going to do this find a mentor…they are worth their weight in gold. I likely would've gotten frustrated and gave up. We've become great friends and someone I look up to with great respect.
Gordy Gritters has some great stuff out there.
Richard Franklin videos are good.
Joe Pie on YouTube has some good machining videos.
John Hinnet (might have last name spelled wrong) has a decent book.
No two gunsmiths do everything the same, figure out what works for you. Also…the old saying if you want to me a millionaire gunsmith, you better start with 2 is very applicable. Tooling is expensive and I spent 3500 on a lightly used Grizzly lathe, I bet I've doubled or tripled that in tooling.
It took me giving up benchrest shooting and 5 years worth of weekends to learn and figure out everything. I'm not a gunsmith or a machinist but I can assemble a very impressively accurate custom rifle. I do everything in house except for cerokote. I now have setup a small business to do this as a part time gig (setting myself up for a potential retirement gig)…2024 was my first year, I lost money but it was expected.
Good luck with whatever you decide…if you're wanting to be a true gunsmith, the school route is the best route.