He is an engineer yes and hes also a genius inventor.
His bio taken from Marvel web
Anthony "Tony" Stark was born to Howard Anthony Stark and Maria Collins Carbonell Stark, owners of the prominent US firm, Stark Industries. As a boy, Tony was fascinated with building and controlling machines. At the age of 15 Tony entered the undergraduate electrical engineering program at the Massachusetts Institute of Technology (MIT), and graduated with two master’s degrees by age 19. Tony went to work for Stark Industries, but showed more interest in living a reckless playboy lifestyle than using his engineering skills