I just published my first print book  with Amazon CreateSpace.
I learned a heck of a lot technically - I wrote it in LaTeX for ultimate formatting control, then ran it through PanDoc and a bunch of my own scripts to massage the epub how I wanted.
CreateSpace make it extremely simple, in all honesty anyone that has used facebook has enough computer skill to publish their own book.
I also learned a massive amount about writing, editing and so forth. Each new draft I kept saying it was "almost done", then would spend months re-writing entire chapters and paragraphs. Along the journey I read many fantastic books about how to write, and how to make my stories more engaging.
It was an extremely rewarding process. The first time you get a draft copy in your own hands is fantastic - it's staggering and the only thing you can say is "holy sh, it's a real book!" Haha.
I'm already working on my next books, and I plan to write for the rest of my life.
 The Road Chose Me Volume 1: Two years and 40,000 miles from Alaska to Argentina - https://amzn.to/2vo3S3G