Publishing a book with Muse?

Add text frames to include plain text. Copy images and paste in MuseScore. You can check out some of the scores by @BSG to see how it's done.

While this is theoretically possible, I wouldn't recommend doing it this way for a book of any significant length. MuseScore just isn't a word processor and lacks basic feature like word wrap, automatic pagination of text, paragraph styles, etc. Instead, I would recommend using MuseScore to create the musical examples then using the image capture tool (camera icon on toolbar) to take snapshots you can paste into your favorite word processor.

@BSG has indeed done some pretty amazing work doing things directly in MuseScore, see for instance https://musescore.com/bsg/continuo3. That's the sort of thing I personally would have used a word processor for, but it's great having the final product be interactive. I've done a much smaller-scale version of that sort of thing, see instance https://musescore.com/marcsabatella/inversion-and-voicing

+1 What Marc Sabatella said.

It depends how many pages and what content and featues you want.
The mentioned examples done in Musescore are great but only a few pages.
For inserting tables you could try to fake them with cascaded textframes perhaps or insert them as image.
(If you would find a way to get tables into a file-format like SVG you would have an image that isn't just a raster picture but is a nice vector graphic and even could consist of true fonts that would make the table text also selectable in an exported PDF.)

You also could try to make the most of your stuff in Musescore, export as PDF and mix these PDFs with a LibreOffice document.
If you are VERY experienced with LibreOffice you can have a look at
https://struckkai.blogspot.com/2015/04/libreofficesongbookarchitect.html

At the blog there are also 2 PDFs made with this. Free Sagreras Guitar lessons (118pages)
and my free Guitar Works (200pages). These examples don't have much content made in LibreOffice (only TOC, pagenumbers, Headers, Extra-Indices) but are just a lot of "merged" PDF scores.