Hey:)

Thanks for reaching out!

Normally, a reattempt for one subject after a five years gap is not allowed under the same board or university rules. Boards like CBSE or state board only permit improvement in the very next exam cycle and after that window closes, the chance is gone. Similarly, most universities set a maximum time span usually two extra years to clear the pending papers. Once the limit passes your registration is cancelled and you can't simply reappear for one subject.

The practical route to start after 5 years is to start fresh, for school level you can enroll with NIOS/open schooling to re-take the subject. And for University you may need new admission into the course or the special approval if the university offers it.

For more accurate answer, could you please tell whether this is for school board (10th/12th) or college?