JEE

Resonance and Allen are the best coaching institute for the JEE Mains. They provide knowledgeable/quality faculty members.

In JEE 2019, 12th marks don't matter to it but yes, you have to secure minimum 75% marks in the board exams, only then you would be able to get admission in the NITs and IITs.

I'll prefer you to join any other coaching institute like Allen and Resonance as the coaching institute mentioned by you is also quite good. But the main problem is that their passing ratio is not that good.

See, you can go through the counselling there. You can get any GFTI and then you can apply for the state universities as going to the GFTIs is far better than going to any state governed colleges.

The eligibility criteria for JEE Mains counselling is to just appear for the JEE Mains paper, whether you have qualified the exam or not.
You are eligible for the counselling, but yes, if you haven't secured 75% marks in the boards exams, then you are not eligible for admission in any of the colleges through Mains counselling.

If you are too good in your academics, try to get the rank below 10,000 for the best institution in ECE after class 12th. It will help you further.

You will get the best institution, because your rank is below 10,000. So chances are there to get good institution for your better future.

It depends on the category, which you belongs to. If you are from SC category, then you will surely get it, but if you from general category, then you won't be able to get it.

Material, biochemistry, energy, biomedical
Bits, DU , GU

No need to wait. Just go for it.