As you have mentioned above that you have scored 421 in the GATE examination with an open category, there is a slightly fair possibility that you would call from IIT's or NIT's.

I would recommend to make a list of IIT's or NIT's you want to apply to and email them your score.

And for the further details, if you have any query you can even visit our website, where there is a detailed description which would be quite helpful for you

https://engineering.careers360.com/colleges/ranking