This was so easy and fun, Katia! I did the cover in Illustrator using pieces I had done previously for a calendar, and the interior using Word. I found a site (that I have no connection to and don't know how reliable it it, but it worked for this) that generates interior pages as pdfs: https://designer.bookbolt.io/interior-generator.php

I made lined notebook pages (the second option) and fiddled in Photoshop to flip it horizontally for the even pages, but it turned out really cool. I'll add a link when the book gets approved, but for now, here's a screenshot.