If you want to deep dive into self publishing try Kindlepreneur.com

There you will find all the information you will need about self publishing fiction or nonfiction. It's free too.

Free courses, free earnings calculators, free facts and direction. They do sell Publisher Rocket which gives you deep insights into categories, keywords, and marketing. They also sell Atticus to format your writing for ebooks and more.

I'm not an affiliate of Kindlepreneur.com or any of their products. In my opinion, they're the best source of info to get your self publishing going.