There are a few common problems with Ford Truck column shifters.
The most common is the linkage under the dash has become loose so it won't shift all the way into Park,.
There are 2 screws that can loosen up, free and easy fix if you know where to look, and have the right screwdriver, lol.
Good video of that fix here:
Another thing that can happen is the the shift cable "jacket" can break, the jacket sets the length of the movement of the cable inside so when you shift it doesn't have full range.
You can see the shift cable coming out of the firewall and then going under the cab to the shifter on the transmission, where it bends the most is often where it breaks or near exhaust pipe.