When the power steering system fails in your vehicle you'll lose your power steering and your steering wheel won't be as easy to turn or control.
If you lose power steering you need to try and pull off to the side of the road and get assistance in towing the vehicle since the vehicle is not safe to drive especially at highway speeds without power steering.
If you're just driving in town and you lose power steering then you can slowly drive the vehicle back home or into a shop to fix the power steering problem.
Vehicles at one time were not equipped with power steering so it's possible to drive your vehicle slowly and safely around town as long as your power steering pump isn't locked up which can shred your belt.
Do get the power steering fixed as soon as possible though and drive it no further than to a shop or if you can to your home and park the vehicle until the power steering problem has been fixed.