Attaching gymastic rings / pull-up bar to the ceiling
You can always run 2x4 or 2x6 across the joists over the drywall where you want to suspend rings and the pull up bar. As long as you secure the board  properly across at least 2 joists (3.5” or 4” construction screws-2 or 3 per joist) you should be good. Not the prettiest setup, but it is quite strong and easy to mount to.