I have a Canon Casio EX-Z3 Digital camera but i dont know how to put sound when im recording a video?

how do i do it

how do i do it or does it have it

some cameras don't have sound
check manual

The Casio EX-Z3 does have sound according to dpreview (http://www.dpreview.com/reviews/specs/Ca... ).

If it's not recording sound, then your camera is broke. There's no hidden feature to enable sound. Either it works or it doesn't. And since it doesn't, then there's something wrong with your camera.