Sleep with lower back pain by lying on your back with a pillow under your knees or on your side with a pillow between your knees for better spinal alignment.
Yes, you should stretch your lower back if it hurts, but ensure the stretches are gentle to avoid further injury.
Planks, bird-dogs, and bridges are the top three exercises for back pain due to their effectiveness in strengthening the core and stabilizing the spine.
The number one best back exercise is often considered to be the deadlift, as it engages multiple muscles in the back, but it should be done correctly to avoid injury.