How do I remove stuck rear lens cap for telephoto lens on D3200

Are you sure you're turning it in the proper direction? Nikon lenses (and thus rear lens caps) screw in the "wrong" way. The lens cap turns clockwise to remove.

If it's an ordinary plastic lens cap, as a last resort you could cut it open with a knife.

Rotate it? Use a cloth. Also, look into a strap wrench. It's plumbers tool that can loosen pipes that nothing else has a chance in heck of loosening. Probably $15-20 but worth every penny. It is my favorite plumbing items since contractor never build with repairs in mind so you have to redo all their lazy work from electrical that does not meet code required screw wrapping to plumbing that uses plumber paste when not required because they have no clue on the proper tension for piping (hand tight plus 1/4 turn). The same rule for screws, add 1/4 turn so it will remain tight for years.

It reminds me of the 5 and 5 rules for for recovering from a stalled airplane modern "pilots" are not trained on. %5 more power and 5% more flaps is all it takes to recover from stalled engine since modern jet planes are so sensitive to air speed.

Yeah, I know a lot about too much, screws, airplanes, herbal infusions, etc. but it does not mean I do not know these not connected pieces of information.