How to design Helicopter?

hello guys,

me my friends decide to design a helicopter for the project.

can u please clarrify some doubts.......😔

1.how can i do maximum power calculation for heli if i know the total weight of the machine?
2.is there any alternative tail rotor (for yaw control and anti-torque)?
3.which type of engine generally used for the helicopter?
4.is there any chance for using more than one engines?


please help me...........................