Hard to know what is causing your hand pain as it is most likely not from your neck. You could have a compressive neuropathy (See: https://neckandback.com/conditions/nerve-entrapment-compression/)
Your headaches could originate from C4-5 (“.C4-C5: Minimal disc osteophyte just abutting the thecal sac. No disc protrusion or spinal stenosis. Mild mild foraminal narrowing C4-C5 from uncinate spurring”) but much less likely.
You could have facet arthrosis from C2-3 or C3-4 which can cause base of the neck headaches although the radiologist did not comment on degeneration of the facets there. It is not uncommon to overlook that finding. A visit to a well qualified pain doctor could be helpful.
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.