I want to calculate the torque required for vehicle to move from rest and have 200kg of mass.

To determine torque you need to specify the acceleration you want the vehicle to be able to achieve and the speed of the engine in RPM. This allows you to use to calculate the force the engine needs to deliver through the drive train to the wheels on the pavement, then the engine power requirement using , and from that the torque from , where = engine speed in radians/sec. This gives the torques that the engine needs to deliver to the drive wheels, but be aware that a typical drive train will cause a loss of about 20% of the engine's power through friction.