What is the evolutionary benefit of coughing?
Imagine you are the first ever life form. Some how you grow to have lungs and when you eat something it goes down into those lungs. (don’t forget evolution is supposedly guiding your formation, so it doesn’t realize you need a stomach or an esophagus for food to travel to the stomach), but it gets the lungs right, but the food goes down the wrong way, and the gods of chance an luck have not had the time nor knowledge to have developed a cough reflex to push the wrong stuff back out of the lungs. So you did, because you were haphazardly formed by the gods chance and luck of the evolutionists.
Evolution did nothing to help any organisms. They were designed and created by God.