Diploma

Hello Yuva Vanka, you are presently doing Diploma in mechanical engineering and after completion you wish to complete aerospace engineering graduation so that you can get a job in NASA. Right? Frankly speaking getting a job in NASA for a non US citizen is quite tough since that being the premier space agency of the country. In addition take on board specialists from different fields of studies like fluids structure materials physics mathematics metallurgy etc. One need not be an aerospace engineer to get employed in NASA for that matter even ISRO here in India. The best way for you is to clear your JEE Mains and then JEE Advanced and get admission in one of the IIT for aeronautical for aerospace engineering course. Your chances for placements will increase and you can also think of doing MS in US subsequent to the graduation in India which will further enable you to get job in NASA. Best wishes to you.