Hello and welcome to JustAnswer!
If you had just lost power steering you'd still be able to turn the wheel, albeit hard. It sounds like you have a mechanical failure, most likely in the steering rack.
What I would first recommend is getting the front of the car off the ground and do a visual inspection to make sure the tie rods aren't bent, nothing foreign has wedged itself anywhere and preventing the wheels from turning, etc. A failed ball joint could potentially make the steering hard to turn but shouldn't prevent it from turning at all, but see if the wheels will turn with the front of the car off the ground. If you're able to turn it with the weight off the ball joints then one of them may be causing the problem.
Most likely the problem is in the steering rack. If the wheels don't turn when off the ground and you can't see any visual problems then I would next remove the intermediate shaft from the rack and see if you can turn the wheels left and right by hand. If not then the problem. is in the rack.