I keep losing power steering fluid from resvoir and when the fluid gets low a loud widing sound accurs. What should I do?

You must have a leak somewhere. The whinning noise is coming from the pump. They make that noise when they are out of fluid.

Are you seeing any puddles or oil drops on the ground under your car?

A power steering resevoir is't very large so it won't take very long or a very big leak to run it out of fluid.

There aren't that many parts to a power steering system either.

The leak would most likely becoming from a hose, a connection or from the power steering component cylinder or box.

My son, when dealing with a failed Dodge pump, found that most people had to replace their reservoirs either before or with the steering pump. There must be a design or material problem with it.

Take it to be serviced immediately. Its extremely dangerous to loose power steering fluid completely.

The sound your hearing is the power steering pump without proper lubrication, this could be a fire risk.

As well as this, your steering could lock up completely and send you off the road. Please see a professional to have this repaired.

There is a leak somewhere , need to locate and fix the leak look under parked car for drips and use as guide to start looking for it