The dryer turns on but the drum doesn't turn, it spins when I manually do it?? Could it be a broken belt?

No most likely your motor is starting to seize up if you can use your hand to spin the drum while holding the dryer switch down and pressing the start button and this causes your drum to spin then the windings on the inside of the motor have become weak and you would need to change the motor in the unit. And if you do order a motor for the unit you should also order a new blower wheel as well because the wheel is made out of plastic and usually when you try to remove the blower wheel from the motor from the rear of the machine 8 out of 10 times the wheel will break because it has been attached to the motor for so long. If you have any further questions message me back and please also remember when our chat has fully concluded to rank how this opinion has helped in your appliance situation Thanks Rick
p.s on the other hand if you can hear the motor running but drum doesnt spin then yes this would be a broken belt issue with you unit