Look left, look right. This is actually an exercise and a stretch because muscles on each side of your neck do opposite things. So the right side of your neck has muscles that both turn your chin to the left and turn your chin to the right. So when you're stretching your chain all the way as far as you can, over your shoulder, you're going to be exercising some of the muscles and stretching the others and this will happen on each side. This helps to balance out the musculature of the neck, and it helps restore range of motion, a healthy range of motion to your neck. Try to keep your upper body still and move your chin all the way over each shoulder.
Holding it there even stretching it Trying to see all the way behind you with your eyes. Do this several times on each side. As usual, holding for two or three breaths. Becoming aware of the sensations. aware of how your breath may change. And over time, you'll see more flexibility and less pain and fatigue around your neck and upper shoulders.
It looks simple, but it's deeply therapeutic and you can do this anywhere.