Hello Aspirant,
I am sorry but there is no chance and no way you can do B.Tech after getting 12% in you class 12 exams as you are considered as a failed student by CBSE but life does not end here you still have along way to go with your life and it was just a minor hiccup in your life.
You should reappear in your class 12 and work hard to get a very good marks in your Boards exam as well as in JEE so that you can achieve your dream of pursuing B.tech and be a engineer.
Hope this Helps.
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