A simple program for writing books?

Question

Books

There is a spherical writer in a vacuum - he does not know how to use a computer, he writes all his "works" in Word, and in the same file. The result is horror and hell. Is there any super simple program for "book writing"? The main requirement is division into sections, a couple of styles (bold, italic and underline is enough), and it is desirable to generate the result in a Word or other type of document. The artist’s work is humanitarian, he himself is a noob, and you don’t want to poke him with markdown or latex

Answer 1

We ourselves are not local writers.
tyts