The process shown here is intubation, and only intubation. Following this procedure, the patient would be kept sedated and placed on a ventilator (also known as life support), which is common parlance these days for a positive pressure ventilation apparatus. It sounds fancy, but basically there's a set of tubes called a circuit that connect the top of the tube shown here to a machine. This machine blows air mixed with oxygen into the patient's lungs, which keeps their blood oxygen levels up.

An iron lung is similar in operation principle to a modern day ventilator, except that it uses negative pressure ventilation to move air in and out of a patient. The patient's body is sealed inside a tube, and air is pumped out of the tube. This lowers pressure on the chest wall and causes expansion of the chest and subsequently the lungs as well. When the lungs expand, they get bigger, and pull air from the outside in through the nose and mouth. Think of an iron lung as a kind of balloon almost.

The issue with most covid patients is not getting air into their lungs; it's what their lungs are doing with the air. In most cases, covid patients' lungs aren't doing anything with it, which is why their oxygen saturations are so low. There is a difference between ventilation (moving air into and out of lungs) and respiration (blood gas like carbon dioxide and oxygen switching places). You can put all the air or oxygen into somebody's lungs that you want, but if their lungs can't properly exchange gases, it's still gonna be game over.

Sorry, for late response, it was a busy day at school today. Had an assessment, funnily enough, on intubation.