You can. Loki figured out how to pee on his bed/blanket and shove it to the side, but he's a little smarty pants. Sammy never had an accident in her crate. Just make sure it's washable
They sell these little crate pads at Petsmart for like $10. They are cheap enough that you can wash them every day and throw them away after a couple months and who really cares. We had 2 so we always had one ready to go. Or you could just fold up a fleece blanket.