BLURB
Our favorite book publishing software at Tiny Seed is Blurb. (Blurb is an American self-publishing platform that enables its users to create, self-publish, promote, share, and sell their own print and ebooks. Blurb offers book-making tools catering to diverse digital skills.) They offer a free desktop software to create beautiful books, magazines, and ebooks, called BookWright. You can download it here.
More Resources:
The 12 BEST Self-Publishing Companies of 2020
Start Here: How to Self-Publish Your Book