Why do atoms move?

According to Kinetic theory of matter: "All matter is made up of atoms and molecules that are constantly moving". But why? What is the deep explanation for the movement (translate, rotation and vibration).

Has it something to do with the electromagnetically forces attracting atoms to each other and some-have changing? If yes, how does it explain heat transfer? What if I isolate single Atom from others?

Or did some time ago one atom hit another very hard and it was transferred to the next and so on?

Al materials I came across just say: "Well if you add more energy, it will move more", what is way to abstract, for example, for developing a simulator.