Start with How I Register My Songs and Get Paid (11 min, JB Sauced Up), then I released 200 songs, here's what I learned (17 min, Jordan Baywood). All 28 lessons here are free, from the teachers' own official uploads. You'll need laptop stand, noise-cancelling headphones, second monitor and a few more basics (about $270 of kit). The book to keep beside you: All You Need to Know About the Music Business by Donald S. Passman.