Welcome to TRS
There are 3 parts to the column shifter
The shifter arm on the column is connected to the Shift Tube, Shift Tube runs down the steering column.
At the other end of the Shift Tube is the lever that is connected to the Shift Cable, this lever is connected to the Shift Tube by two screws which are what often loosen up, the common issue.
When you move the shifter arm it turns the Shift Tube which turns the lever on the end and pulls or pushes on the shift cable.
Shift cables other end, pulls or pushes on the Shift linkage(on transmission) which turns the Shift Rod in the transmission to select gear
Binding could be shift tube issue, it is held in place by 2 "caps" if they loosen up then shaft can bind, or shift tube can crack/break.
Video here on shift tube:
www.youtube.com/watch?v=I6v7iagT-NE
Could be at transmission end as well.
Block the wheels!!!!
Shift transmission into Neutral, shut engine OFF if it was running!!!!
Remove shift cable end from transmission linkage and shift transmission with your hand
Should be easy to shift between Reverse and 1st, PARK can be hard which is why you put it into Neutral first.
If it is hard to move/shift linkage and there is no obvious sign of external problem then shift rod IN the transmission is binding.
But that is a long shot, most binding or looseness is in the column to trans shift system