Hello Prabha,
First of all don't worry and also ask your brother to get relaxed because nothing is going to happen to you.
The issue you have mentioned will not cause any problem and the result which will be used in NEET UG 2022 application for class 11th and 12th should be of the same state board from where he had passed the examinations and it will be considered. Even in counselling only the result of state board will be considered so make sure that he will have a valid result from the state board.
You have to take care of the fact that you should never share the details of class 11th from CBSE board anywhere and even that will not be considered as valid because you have not completed class 12th from that board and as you have completed 10+2 from state board so you should mention only about your state board wherever you need it.
So now get relaxed because no action will be taken against your brother.
I hope you got the point.
Good Luck!!
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