A torsion bar is a suspension component which acts as a spring by the twisting action of the bar.
It is located on each frame rail spanning from just under the middle of the front door to the lower control arm. It is inserted into the arm via a hex hole.
Cranking them means to adjust the adjustment bolt to either a: raise the ride height or b: cure sagging bars. You're doing both by cranking the adjustment bolt. Sometimes called a TT: Torsion Twist.
Here's a torsion bar and it's location...(arrow pointed at adjustment bolt)
Here you'll see the full length of it. They are the two bars parallel with the frame...
They are found on 98+ 4x4 Rangers/B-series, as well as 00 Trailhead 2wd, '01-05 Edge 2wd, and '06-08 Sport 2wd.
Judging by your avatar, you've got a 98-00 2wd coil spring truck. You do not have Torsion Bars.