Not being able to crack jee is not an issue at all, there are various private engineering colleges which have teaching facilities better than what you would get at an NIT or IIT. There is only one thing you should keep in mind, it doesnt matter whether you study from a tier 1 college or not. In the private institute or state government college, you would still be getting ample oppurtunities if you work hard. You should enjoy the college life and just keep at back of your mind, that you have to get a good placement, and for that you have to work hard as you might not get excellent placement oppurtunities as you would get in a tier 1 college. You should choose your field wisely and you have to work hard on that and many off campus oppurtunities will come your way. Keep a good friend circle, make projects, participate in student activities, engage in clubs and societies and you will have fun but keep in mind what you came for study hard and you will get a good placement.