Yeah, I imagine the amount of books by language depends on the library. Mine has 2k German and some Dutch and Ukrainian as well - didn’t vet those. I was able to download an .acsm file via Manage Loan -> Read with… -> Epub, but then you still need to deal with an acsm file - definitely not a real solution, just figured I’d mention it

For my local library, I noticed they have both Onleihe and Libby available - though with different selections, ymmv

I second Duolingo and Drops for mostly vocabulary learning, and then I’d supplement with a textbook for grammar and a more structured learning experience. I keep seeing the everything learning german book recommended, but really, just choose whatever looks reasonable and go through it doing all the exercises

Going from your sidebar, how about art gallery?