You can apply for Class 12th Improvement application form to follow the guideline.

Procedure to apply for the CBSE Improvement Exam

• Visit on the official website www.cbse.nic.in
• Download the application form
• Fill the form with accurate detail
• Submit the form with one photo state copy of marks sheet.

The application form is expected in this week of September or First week of October.

If you explain your 12th score then only I can help you that you required to apply or not.