Since I’m seeing Libby mentioned a lot: for those in the US, check the libraries in the large cities in your state, too. Sometimes they have digital-only cards available for statewide residents. You can have several library cards on Libby so you have lots of options!
Also check your area for Little Free Libraries, which are free “take a book, leave a book” boxes!
Yes, and there are libraries with cards for non-residents, too! That's what I use on Libby. These are typically not free, but some are low-cost. If you don't have a library card already, this is a great way to get one without having to drive somewhere. For example, according to this list, Fairfax VA charges $27 per year for access to a catalogue of "over 50,000 ebooks and 21,000 audiobooks".