Even if babies can’t sit through an entire story, they can interact with books, and every interaction is good. Holding a book and turning its pages are great practice for reading someday. The more familiar babies are with books, the more likely they are to pick them up to read when they’re older.
Talking about the cover or the pictures inside shows kids that pictures are a part of the story. You don’t need to get through all the pages, pictures or even past the cover with really young kids. The important thing is to make book time fun.