Hey Saurav,

Most Colleges It's required for you to pass Your 12th standard for further Admissions. And then only you will be issued pass marksheet by your school board. In Bihar Engineering Colleges. So you should reappear for your improvement/Compartment exams. Here is criteria of eligibility in Bihar Engineering Colleges.

https://engineering.careers360.com/articles/bcece-eligibility-criteria/amp

Best of luck