When I start my dryer to dry clothes, it squeaking noise, it's a GE front loader

Generally its from a bad bearing, but it can also be the belt or belt tensioner, they use a large belt to turn the drum with a tensioner to keep the belt tight, and the whole drum spins on a bearing located in the back of the dryer in the center. You can change them yourself by pulling the top off, (it just pops up by prying ) then removing the from screws located inside that hold the front on the dryer (note:the drum is light weight but it will try to fall when you pull the front of the dryer away, so be ready to catch it), then inspect the belt for wear and make sure the tensioner looks like its doing what it should, keeping the belt tight, then inspect the cloth like material they use as a cushion for the drum to ride on, you will see it on the from panel around the door, and there is also one in the back that is much larger, if one is missing it will sqeek, and if all that looks OK then you will have to loosin the belt and pull the drum out and replace the rear bearing, they run about 25 on GE's, hope this helps