Dear aspirant,Kudos on clearing JEE Mains exam.This answer is solely on my perspective.On comparing both the colleges NIT-warangal is far better than COEP,but while comparing branches Mechanical is much better than biotechnology based on many factors.But if you seriously inclined toward biotech branch you must go for NIT Warangal.But according to my perspective NIT warangal biotechnology is better than coep mechancial.

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