Reposting this because I have no idea why the Janny deemed it deletable:
There's a site called the Homebrewery that was designed to let people do homebrew 5e content.

Everything I did was Markdown and the stains from this site: https://watercolors.giantsoup.com/phb/

https://homebrewery.naturalcrit.com/

You could probably get an AI to set up the pages for you and so on actually, but I'm just a simple grug who did it all by hand.
My basic process is
>Grab raw chapter
>Add markdown for question boxes, vows, ect
>Throw into the homebrewery editor in a block
>Find where there are natural breaks and either new column or new page it
>Check for where images seem to fit in naturally
>If there's something that really needs an image like an NPC (pic related) then break it up intentionally to fit around those things or do a new page for a full page image
>Once satisfied a chapter hits my https://www.youtube.com/watch?v=vjUqUVrXclE requirement move on to the next one

The next 30 pages took me maybe 2-3 hours of half-assing it, which included image editing and so on.

Hope that helps?