According to the national map, you are not allowed to bring your own books, but exercise books and the like are still possible. Packages and other things are in the locker. If you really want to bring any books in, you can try to carry them in a portable plastic bag. If not found, of course, it is also possible. If you find out, you should just give a warning. Nothing will happen. Of course, water can be brought in. Of course, there is water in it. You can take a water cup and drink water in it.