Boneless wings are deep fried chunks of chicken breast.
Chicken nuggets are a random assortment of pieces of several chickens' bodies that have been ground up into a paste and emulsified with other mystery ingredients, dyed pink, and squirted into a plastic mold to be reconstituted into a solid before being deep fried.
At least that's generally the case. You can tell the difference between actual meat and reconstituted meat because muscle fibers have a grain, like wood, which runs in one direction and will only easily come apart along that grain, whereas reconstituted meat comes apart like styrofoam.