Mechanical Engineering is one of the oldest branches of Engineering. It is also known as mother branch of Engineering. It is most fundamental field of Engineering. Mechanical engineering skill set and knowledge will be one of the biggest driving force behind product development , innovation , Intellectual property ( patents) and quality of manufacturing in India.

Career:
The most important fields in Mechanical Engineering are:

Structural Engineering
Petroleum Engineering
Mining Engineering
CFD,CAE. etc
Aerospace Engineering
Mechanical Engineers get decent jobs in automobile industry, space research, energy, aeronautical, air conditioning, medical industry, turbine manufacturing plants, oil and gas plants. They can work in private sector that provide technical consultancy to both corporate and government companies.

Note : There is good scope of ME so if you have keen interest in this branch then you should go for it.

Hope this helps!!!