How can I give users access to downloadable files from the homepage of my webbook?

If you're on a PressbooksEDU network, check out https://guide.pressbooks.com/chapter/distribution-exported-files/

If you're a Pressbooks.com user:

This is PressbooksEDU feature that isn't available on Pressbooks.com. However, you can always export and download the PDF and ebook files, then distribute them through other means. 

If you'd like more information on how to acquire a PressbooksEDU network, contact [e-mail].