2001 Cadillac Deville Drivers front wheel feelsl like no po

2001 Cadillac Deville V8 Front Wheel Drive Automatic 115K miles

Heard a loud "whistling" sound about 2 weeks ago, when turned the car off. Drove car with a slight sound similar to a jet engine. Went to make a hard left turn felt like car was turned off, as I accelerated realized next left turn no power steering. No problem with passenger side.
Thank You
Denise Tasch