Hello,

if it doesn't match at the center then they will not allow to give the exam. This will happen if they will verify biometric at center. generally they just take your biometric in a attendance sheet which is provided by the board. That paper is matched with your biometric thumb impression later.

If it will not match then your answer sheet will get rejected and your application will get canceled.  Don't think too much for now. If there will be anything wrong then you will get notified by the board anyway.

Meanwhile try for other entrance exams too. Physics and chemistry is mostly common in exams and for rest you either have to study General knowledge, biology and maths. it will be one or two of the three.

Keep on studying and practicing. everything will go well.

Hope it helps!