The basic principle behind the flight of both aircrafts and rockets is Newton’s Third Law of Motion, which can be stated as, “Each and every action, has an equal and opposite reaction.” Both rocket and aircraft burn a combination of air-fuel and the resultant gas is ejected out of them. This action of hot gases produces a reaction in opposite direction propelling the flight of an aircraft or a spacecraft. So both eject hot gases to gain momentum which helps them to fly.
While both of then fly by the burning of air with fuel, the mechanism of it is different in both the cases. Let’s not forget that rocket serves the purpose of flying into the space while aircrafts and aero planes are restricted only to the earth’s atmosphere.
Keeping this fact in mind, we can understand why aircraft can use the atmosphere from its surroundings to fly, but rocket can’t –because there is no atmosphere in the space.