https://www.masteringemacs.org is the best books on Emacs I have ever read. But truly, is just about doing things in Emacs. Start using Emacs and whenever you need to get something done, just google it. After a few days, you'd have sufficient vocabulary to navigate yourself around. Don't be obsessed with configuring and adjusting it to your needs at that point. Jump into that rabbit hole later, when you feel you know what you're doing.