Q.What do I do about dying or sickly shrub
We moved into my parents home a few years ago after they passed away, so a lot of the plants/shrubs were planted by them. There are rhododendrons, hydrangeas, plus plants.
This bush/shrub has ceased to leaf out or bloom at all except a few branches along the right side. The leaves that were on it when we first moved in were turning spotty and dying, I did trim back some of the overhang of tree branches above it so it could get more light.
Wondering if I should prune most of it back? Remove it completely? Or what else might help?

Certified GKH Gardening Expert
It's hard to tell what this plant is but you are right - the dead parts need to be pruned away and, if I were you, I'd prune back the entire tree/bush to give it a fresh start in spring.
Here's a good article on rejuvenation pruning:
https://www.gardeningknowhow.com/ornamental/shrubs/shgen/rejuvenation-pruning-tips.htm