Hello Ashish!

There are job many opportunities for a mechanical engineer graduate. Though it is less than other branches like CS, EC etc, you can still find a number of ways.

You are since talking about IIT graduate, you are likely to get placed in one of the top mechanical companied visiting campus. If not, you can apply outside campus too.

If you don't want to continue in your field you can make a shift to IT industry. You have to learn programming, computations, algorithms etc.

You can pursue MBA. It is one of the most well known choices among IITians.

You can give Indian Engineering Service exam. It is a governmnet job and you will be employed in different departments such as defense system.

Civil service exams are yet another option. If you are interested in higher studies, pursue M.S or M.Tech. You can do research or become an entreprenuer too.

It all depends on your interest. All the best!