Power sterring is diffulcult, barely can turn sterring wheel.

Check the power steering fluid level.
If the fluid level is low, you obviously have a leak somewhere and it should be repaired. If the level is up, watch the power steering pump while the engine is running; is the pulley turning freely?
Power steering systems are hydraulic devices. The pump provides the pressure and the steering gear or rack and pinion assembly (depending on the vehicle type) applies pressure in the direction that you are turning the wheel to assist with the steering. When the hydraulics fail or when the internal components fail, your strength is the only thing turning the steering.
But start with the fluid.