After dropping 2 years I got an admission in NIT Jamshedpur in the CSE branch. Will it affect the placements?

When it comes down to whether or not a decision affects your placement, it, first of all, depends on how you have prepared and put effort into your studies. If you have not put much effort into your studies and have rather studied in an unresponsive and impassive manner, then a bulk of companies actually rejecting you is more obvious.

If you want to pursue your goal and more often than not, have prepared to not let any individual material affect you, then these are ways you can aim with:

1. Aim for your Academia: You should have a checklist of several professors from various other universities who can lend a hand in providing you research-oriented topics to further work on during your summer breaks. This is one way by which you can aim at greater selection, only if you stand out in the project.
2. Aim for a Lucrative Job: You should always aim to participate in different algorithmic contests and contribute to your open source. It will help build a reputation and can gain you exposure in the industrial side. It also will help see the capability to sit through various contests or examinations and stand out with solving numerous demanding questions. This is another way recruiters will find you as a great asset to their company.

Other than that, you can always go up for management and courses other than the one stated above. It however depends completely on you.