Most likely the serpentine belt, when you rev the engine does it get louder, once the car runs for a minute does it go away or it may still do it.....If this applies most definitely I would have the serp belt checked or changed...
Power Steering pump my have a leak...
rear differential got lube? rear wheel bearings?
A worn belt will cause a squealing noise. The squealing noise is caused when the belt slips. Tightening the belt will temporarily fix the problem.
Check the belts. The most common cause of squealing is a worn or loose belt on the front of the engine.
It sounds like you have a belt that slips when you take off. This will cause a high pitched squeal.
lack of oil
When refilling the oil some may have dripped onto the belt which would cause it to start slipping badly and squealing loudly.
A loose or glazed "fan belt" is a very common cause of squealing. A quieter squeal is produced by brake linings that are almost worn through.
Turning the steering wheel farthest left or right for a few seconds will cause a loud squealing.
AC Compressor
Yes.Equally likely is if the belt is much more than 3-4 years, the material is glazing over or hardening, which is another common cause of squealing.
The cause of the squealing sound is because you are turning the steering wheel completely to the right or left