it is probably that your shift lever bushings have worn out, but check the rubber seals and carpeting, sometimes they put pressure against the shifter making it pop out of gear.
yes it has reverse and both high and low range gears . i can get it to run in both forward and reverse but only in low range . when i shift IT into high range it is still running in low range .
if it was automatic it had a torqueflite tranny and had 3 forward gears and a reverse and if stick shift you had either a 3 speed tranny (rare) or a 4 speed.
You may have to have your clutch adjusted,
Odds are the clutch is in need of a adjustment or replacement.
Your forward gears are in a standard "H" pattern. To engage reverse, bring the shifter all the way to the left then push it down and pull back.
car will jerk forward and then go in reverse
it could be the shift linkage being that both gears over there wont work
could be either transmission shift linkage not engaging reverse ( stops at neutral ) worn joint connectors sometimes cause this. or reverse clutches or gears bad inside transmission.
In the car there's a small hole by the shift gears, take cover off, we used a metal nail file To press down, this now lets you shift gears.
The gears in your transmission may be sticking or worn out. This would cause your transmission to not be able to shift.
Shift linkages not put in the correct spots.
shift into reverse gear