Hello Aspirant

If you were a regular candidate (enrolled in a school) and were absent from a theory exam in your 12th board exam, you can indeed appear for all theory exams the following year as a private candidate.

This option is typically available to students who were unable to complete their board exams due to unforeseen circumstances.

You just need to fill out the form as a private candidate on the CBSE Board's official website before the exam.

Hope this helps