How do atheists explain the laws of Universe to work together without ever interfering to create chaos?

Stars do collide with each other - not 'all the time' because there is quite a lot of space between them, in case you hadn't noticed. Jupiter's gravitational field is so strong that most comets and asteroids which could be a threat to us will collide with that planet instead, but there have been impacts in the past and certainly will be again. So the laws of the universe do 'interfere to create chaos', if you wish to put it like that (though I wouldn't).