I have a terrible pain in upper back neck area. What precautions I can take while walking n sitting?

Posture n rehab. Proper posture when sitting or walking, good support and seatin helps. Lifting and getting up with your knees instead of jerking with your neck and back is wise. Of course the question is y is there so much pain - seeing a spine doctor or rehab medicine doctor might find the cause or lead to physical therapy which can strenghten, help and teach good body mechanics.