My shoulder is popping and grinding with pain. it pops and grinds while rotating it. what could be the cause of this? do i need surgery to repair?

Need a careful histo: ry and physical exam and then some imaging tests and maybe some lab tests to establish a sound diagnosis. With that in hand, a rehabilitative program can be devised for you which MIGHT involve physical Therapy and might involve surgery. In general, the most conservative approach (non-surgical), though longer, works best in the long term.