How To Treat Shoulder Tightness And Neck Pain?

Hi I have tight upper shoulders and neck pain .when I turn my head and my spine is not fully straight I.e. Sitting my neck vertebrae seems to click and I have limited muscle movement with range of motion without muscles feeling tight and neck clicking sound .i know I have limited arthritis in neck could it be worse or is it muscular or what ? I have been exercising but still not helping ?