I replaced the dyer belt on my ge dryer 3 years old by the way and when I put it back together and pluged it in I have no power at all no lights nothing

You either have the breaker or fuse for the outlet turned off or disconnected a wire when replacing the belt. If the outlet shows power, open the back of the dryer and look for a loose or disconnected red, black or white wire. Is this a gas or electric dryer?