Please help y dryer knob turn and pushes in but the dryer doesn't turn on. What can be the problem? Hopefully it's something I can fix due to no money.

See if the Door Switch clicks when opening/closing door.

It does click closed

Door switch is what you hope for, could be the Door Switch. Verify Power to the Receptacle.

You didn't say what brand. Some dryers have a thermal fuse that will not allow the dryer to come on if it is blown.