Congratulations for scoring this much rank in JEE Mains 2018.

Since you have not mentioned your state of eligibility I am considering you from orissa.

Since on this rank which you have secured it is not possible for you to get any National Institute of Technology or Indian Institute of Information Technology.

It can be if you are from any other state.

http://tools.collegepravesh.com/college-predictor/jee-main/

Visit this link and enter all your credentials so that you can get the correct idea of what colleges you wull be getting.

Joint Entrance Examination (JEE) is an engineering entrance examination conducted for admission to various engineering colleges in India . It is constituted by two different examinations - Jee main and the JEE Advanced . The exams are of the objective pattern. JEE Advanced is regarded internationally as one of the most challenging undergraduate admission tests.

You can also look for other private colleges and should wait for counselling of other engineering entrance exams