Yes, you can give your 12th exam from another school. However, the process may vary depending on your board and the specific rules of the new school. Here's a general outline of the steps you might need to follow:

1. Contact the new school: Inquire about their admission process for 12th standard students. Ask if they accept students who have already completed 12th from another school.
2. Gather necessary documents: This may include your 10th standard certificate, 12th standard marksheet, and other required documents.
3. Submit the application: Fill out the application form provided by the new school and submit it along with the required documents.
4. Pay fees: You may need to pay the admission fee and other necessary fees.
5. Enroll in the school: Once your application is approved, you can enroll in the school and start attending classes.

It's important to note that the specific requirements and procedures may vary depending on the school and board. It's recommended to contact the new school directly to get the most accurate information.

I hope this information helps you.