Certificate

No, without a higher secondary certificate you cannot apply for B.Tech. It is proof that you have basic knowledge of B.Tech subjects and you have passed in class 12th. It required at least 60% in 10+2 to get B.Tech in any college.

Yes, if you have NCC certificate then you can apply for B.Tech.
Good luck.

See, there are two governments which issue category benefits according to their need in the state and country. So, state marks some category and centre marks as well. So, every person has to issue two certificates one of state and the other of centre but as Delhi is not a state but a union territory, I think you have to issue only one certificate that is of the centre.

All students have to submit medical report as per format given in JoSAA brochure.

You should need to clear one exam which is called SAT to get the admission in foreign countries and specially in United States.

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Thank you.

Its depend on the area where you have to apply. Generally with in a week.

It should be updated and only made 5-6 months before the counselling.