Do chimpanzees use simple tools

Yes, the chimpanzees can be trained to hold and use tools. They are quick learners and can be taught many things.

Yes, they can because, like human beings, they have what is called the "opposable thumb". This means that they can place their thumbs opposite their fingers (with the thumb lying across the palm of the hand. They can also make a fist. This human type of hand enables them to hammer with the fist, to pick things up between finger and thumb, to hold their babies, to grasp a tree branch, to hammer with a rock and, in general do whatever hands enable we humans to do.