If you passed your 12 th in 2016 or before then you are not eligible for jee mains else you can apply for jee main and crack the exam with a good score to get an admission in top NIT or IIIT. YOU HAVE TO work really hard to achieve it. JEE is one of the toughest exam in India. So prepare well.
Hope it helps!
As you know that jee main allow only three attempt for a candidate to appear in jee main... but as you mentioned you are also aiming VIT SRM and other best or top private colleges years after 12th and 2 years dropper you can go for best private colleges like Vit, SRM ,LPU and other colleges.
All the best!!
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