Hi aspirant
Once you complete your intermediate you can appear in entrance exams like JEE Mains and JEE Advance.
If you want to take admission in NITs then you must appear in JEE mains .The exam is conducted twice a year and it consist of 90 question for 360 marks in total.
Physics: 30 question X 4 marks each=120 marks
Chemistry: 30 question X 4marks each=120 marks
Mathematics: 30 question X 4marks each=120 marks
You can fill the form next year because this year both sessions of exams are over.There are around 31 National Institutes of Technolog in India in which you can take admission on the basis of JEE mains.
Visit here to know more about this exam: https://engineering.careers360.com/exams/jee-main
All the best.
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