Dear candidate

Yes It is possible, he can study 12th as many times he want; for that purpose he just need to enroll himself next year and again study 12th and write exams. Well he can also write the remaining exams as supplementary but he cannot write betterment for the three exams that he had written already but if he chooses to do 12th again the procedure is just same as he did to join 12th for the first time.

Hope this Information is helpful.