Can you sit in a squat position for longer time without falling or without any pain? If yes, you are under the few people especially in the western world who can do this.
But believe me. In some point of your life it was no problem for you. Because this is a natural human rest position which relieves the pressure on the back. People in other cultures still sit like this for hours without any problems. Our body just forget how to do this because we are sitting all day.
Try to sit 30 minutes throughout the day in this position. You can do this anywhere. Just let your timer run on your phone every time your go down.
Depending on your fitness level doing this challenge can overtax your body. Build in rest days so your body can adapt to the new situation.