I have lower back pain and cervical spondylosis. not able to stand on my legs for long duration. need advice.

Spinal stenosis : If you have arthritis in the neck (cervical spondylosis) then you will likely have arthritis in your back (lumbar spinal stenosis). When you stand, then gravity takes over. The overgrown joints and ligaments compress the nerves leading to leg pain. Sitting or leaning over a carriage in the supermarket takes the stress off the low back. See a spine expert for evaluation and treatment.