To qualify for NDA , you must either be appearing or have  passed 12th grade in any board . Since your brother hasn't passed, he has to write NDA only after clearing his physics paper . There is still hope , don't you worry about it at all. Just focus on the exam.

Dear student,

This is to inform you that this won't create a problem because you have already applied for making the necessary changes therefore even if the card details do not get changed before 11th January you can definitely submit/apply the documents. There were certain instances where the marksheet had a different name and Aadhaar card has some small changes , its just that applying for correction is absolutely required and you have done that so you need not worry and can apply easily.

Dear Student,

At first you need to decide that in which field you want to be a Officer and to be a Officer you need to complete at least your graduation degree then only you will be eligible to be a officer in any field. You can choose any course in any of the university to complete you UG degree, here is the name of some good university you can consider to take admission for your course.

• Delhi University
• Banaras Hindu University
• Aligarh Muslim University
• Allahabad University
• Madras UNiversity
• Jamia Millia Islamia
• Jawaharlal Nehru University
• Anna University
• University of Hyderabad
• Jadavpur University
• University of Mumbai

You can take admission in any of these by giving the entrance examination then after completing your course you will be eligible to be a officer in any field.

Good Luck :)