Picked up the car very recently, so most of it is new to me.

The mustang has a handle under the dash which you pull to activate the parking brake, then twist and release to deactivate it. Recently, the twist and release part has been breaking down, to the point where you twist and nothing happens, the parking brake is still engaged.

With the parking brake permanently engaged, the car is hard to accelerate (obviously) but also will not stop once it gets going. The normal brake pedal does nothing, no resistance when pressed. The parking brake doesn't seem to prevent the car from moving in reverse, but again, there is no way to stop it, except switching to park which is terrible for the transmission. How would I go about fixing this?

Haven't tried jacking it up yet because the vehicle is parked on a busy street. Finessing it into my driveway with the parking brake engaged and no normal brakes would be a nightmare.