How long can one lung breathe?

People always have five brain lobes, but not all of them are fully used in daily life. Many parts are at rest. When the activity increases, they need oxygen to move. If it has been a long time now, the patient should have tolerated one lung, and there should be no problem when there is little activity. But in this case, the lungs have no compensatory ability. If this lung is infected again, it will die.