Girls, tell me, is it just us like this?

Girls, tell me, is it just us like this? The baby keeps sucking on everything and laughing at me when I scold her and try to take out what she shoved in her mouth. She starts eating a book, but when I say "ah-ah", no, run away from me and laugh ? She can't understand anything. I don't allow her to climb into the closets, so she doesn't go in there. Only with her mouth like that.