Hello Mukesh !

Aerospace engineering is one of the primary field in engineering and requires a B.tech degree with a minimum passing percentage. 

Areas of specialization of aerospace engineering are :-

1. Aeronautics

2. Aircraft and spacecraft guidance and control

3. Navigation

4. Space and atmospheric flight optimal control

5. Small satellites 

6. Aerodynamics 

7. Space mission design and planning

8. Spacecraft and vehicle design

There are many other areas of specialization

All the best !

Hello Mukesh,

Broadly Aeronautical Engineering can be classified into 4 specializations -

Aerodynamics - This deals with the basic property of flight, the science you must know if you want a body to be aerodynamically significant

Propulsion - This involves the propulsion systems of an array of aircraft and rockets. It deals with chemical science and the physical structure of the propulsive components in the aircraft.

Avionics - This deals with electrical systems and electronic systems on board the aircraft. From pilot display to navigation systems, everything comes under this specialization.

Structures -This deals with the structural perspective of an aircraft body. Weight, strength, density, corrosive resistance, tensile strength all play a major role here.

Although the 4 are specializations there are a variety of classifications as well. 

Good luck!