Hello Sarthak,

It is possible but for that, you have to represent some genuine reason to CBSE for your decision. Normally you have to do your +2 from CBSE same school and from the same board. But sometimes exceptions are made. If you have a real genuine reason to change your board then go ahead and try. There is no assurance that you will be granted your wish but still give it a shot, who knows.

Good luck!