Hello,
Since, CBSE had started using the term RT instead of FT from 2020, so let me clear few of the facts to you. CBSE gives atleast 3 chances to clear your exam if you failed in one or two subjects that is known as compartment exam. CBSE will provide you the first chance in the month of July - August , second chance in the month of April - May of next year and third chances again in the month of July - August of next year. If, you failed to clear in these three attempt then you have to appear for the complete class 12th boards again. Remember if you have failed in one or two subjects then and then only CBSE will allow you to take compartment exam else you will be considered as fail for the class.
Nextly, if you passed and think you want to improve your marks, then you can appear for improvement exams, but keep in mind that now a days according to CBSE your marks in improvement exam will be considered as final marks, as per my knowledge, still just clearify the fact with you school officials as they know the fact much better then me.
Hope, this will help you.
Thank you & Good luck!
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