Help! Pedal has to much resistance that i cant pedal bbshd

[Abzy]

Hi I can't pedal on my bbshd I took the chain off and it's easy to pedal I but as soon as I put the chain on my bike it has a lot of resistance to pedal do you know what I can do also when I go out with my chain I can use the throttle to move the bike but i can't pedal it even if I'm trying to jump start the pedal by using throttle can someone help me