i have 2004 chevrolet suburban and the air and has stopped blowing what is the problem?

Blower motor, its relay or resister or its fuse if no air at all coming out or if you hear it running and no air then flapper door stuck or broken flapper door. The switch selector same thing could be relay, fuse or switch cluster.

I can't hear it running. No air or heat is coming out

Then the resister or relay or blower motor, All three are under/behind dash passenger side toward the middle. The relay and resister is on the blower motor or it housing or the wire harness at blower motor. You can use a bypass procedure for those two and run battery power to motor to test whether its o.k. and there are some testers you can buy to test relays but you can also buy one try it out and if that does not fix it take it back for refund.

Be sure to check those fuses too.