I have clumps of pine needles and pine cones that fell from a red pine tree
Covering the ground. The clumps look like they were chopped off the tree.
There is only 2 pine trees that this is happening to. There is a lot of clumps
Covering the ground. It looks like someone covered the grass with these
Clumps. What could be doing this

It may be just the natural processes of the pine tree. The clumps of needles - are there any branches attached to them? Or is it just clumps of three or five needles? Pine trees grow needles in clumps (different numbers for different types of pine trees), and these occasionally fall out, the entire clump at once.

If you've actually got branches breaking/being cut off the tree, then that's something completely different. It may be the result of wind damage, pests, or vandalism. I'm afraid I can't offer any help if it is pests.