Complex sentence: He enlisted in the Air Force at the age of 19, because his brother was then serving in Korea, and through the Aviation Cadet program, Class 54-G, received his commission and his wings with a rating of pilot.
Split into simpler sentences: He enlisted in the Air Force at the age of 19 because his brother was then serving in Korea. Through the Aviation Cadet program, Class 54-G, he received his commission and his wings with a rating of pilot.