You can borrow e-books from libraries, but they come with DRM which means that they can manage “loans” and “returns” so they have a nominal number of books to lend out.
Quite a good service actually, called Libby. There are obviously ways to remove the DRM and make just a normal ePub but I’d quite like not to have to do that if I don’t have to.
The most frustrating is that store, even searching for the most popular books yields weird, useless results for me.