Hello Priyanka, you can do MTech in any of the engineering collges both in India or abroad. To get into any of the IITs or NITs, you need to seat for the GATE exam, and based on your rank you will get entry. For other colleges, most private colleges have their own selection criteria or exams or may also depend on the GATE scores to provide admission.

With a good rank in GATE, you could also be eligible for a PSU.

Please check out these links to get a better idea about GATE:

https://engineering.careers360.com/exams/gate

https://engineering.careers360.com/articles/gate