Hi

You seem confused regarding what to study for a good internship and placement and I would like to say welcome aboard. This is case with every student, irrespective of the branch. Being in an NIT already provides you ton of options to explore from and that is exactly what you should do! Explore your interests. There could be a statistical answer i.e. you focus on coding and computer languages like Python, C++, Java etc. however, this will give you an edge in placements because of vacancies specifically for software engineers and jobs alike but this will not work if you have no interest in reading those languages because then you have to study mechanical as well as computer courses. I apologize if this confuses but the truth there is no exact answer or solution. You made it to NIT and then you can go further ahead too!

If you have a further specific query please feel free to comment.

Best of Luck.