Q: No power steering, no power, no lights

Does the vehicle start and or run? When several systems are effected it is likely a wiring issue. You may be experiencing failure of the fuse box panel, or major electrical ground somewhere. If you own a voltmeter, you can trace electrical power on these systems and find where the drop occurs. The power steering is heavily dependent on the engine performance. If the engine is not supplying the pump and system with enough power, the power steering will fail. If the heater core is not being triggered or activated when the heat is turned on, the valve will not allow hot coolant to enter the heater core to warm the air coming through. Electrical tracing and inspection needs to be priority in order to track down the culprit.