I have a shower that has not been used for a long time. Today I tried to pull the single faucet handle but it was real hard to and when it worked no hot water came out- please help

Yes, washers and O-rings get stiff inside the faucet when not in use for longer period. Also, calcification will make handle to operate harder than usual. Do this:

1. Close water to the whole house
2. Remove handle and cartridge
3. Soak it in vinegar
4. Reinstall

Or, purchase new cartridge and replace the old one...