It is called pavanmuktasana as it releases the trapped air in the abdomen. Go to sleep. Then raise the right foot slightly and fold it near the knee, hold that knee with both hands and press that knee firmly on the breast of the right chest. Hold for 5/10 seconds, release arms and reset by extending legs. Then place the left knee on the left breast in the same way and press hard for 5/10 seconds and extend the left foot and restore it. Perform the action by pressing the left and right knees firmly to the chest. After performing this action in both positions separately, both the knees should be folded in the same way and pressed to the chest. First the right knee, then the left knee, and finally both knees pressed to the chest for a while, then the posture is extended and reversed, and the action is performed only once. Similarly perform the action 4 times. No need to pay attention. If the action is well mastered, bring the knees to the chest while inhaling. Hold the breath as long as the knees are pressed to the chest, then extend the legs as you exhale.

The asana practice in which the trapped air in the stomach is released - that asana is called Pawanmuktasana.