Both degrees of Mechanical Engineering are completely different. If you were to take up a B.E/B. Tech program in Biotechnology, you would most definitely have a different skill-set when compared to a person who takes up a B.E/B.Tech in mechanical engineering.

With a B.E/B. Tech, you study all the engineering disciplines in the first year (Mechanical, Electrical, Electronics, Programming/Comp Sci., Civil, CAED, along with engineering math, chem, and physics), but what you study will only be the basics. From the second year on, biotech students are introduced to basic biology, biosciences, unit operations, and bits of chemical engineering. On the other hand, mechanical engineering students delve into machines, their operation, and possibly how to make them (I’m not entirely sure what they study). This makes both disciplines eligible for a completely different set of job opportunities.

Coming to Aeronautical Engineering there is a much scope if get a degree from IIT so that you can get a placement best companies of salary package of 14LPA.

Best of luck.