After completion of graduation, what is the logic of doing some course whose qualification requirement is Class XII that I did not understand. Your brother should do any course whose qualification requirement is graduation.
I recommend him doing MBA (Ops). His knowledge of Stats will be of immense use to him.
After MBA (Ops), one of the best thing for him is to get into Supply Chain Management (SCM). SCM requires lot of calculations. With his background in Stats, he should not have any problem in SCM.
Supply chain is growing world over and India is no exception. Therefore, sky is the limit to grow in this field.
I conduct the training programmes in the field of Purchase and Inventory management. My observation is that non-engineers do not succeed much in this field because of their poor mathematical skills. Your brother may check the website of Indian Institute of Materials Management (IIMM) and do the course of SCM.
One more course is on Operations Research (OR). This is quite old one. Your brother can check website of Operations Research Society of India. With the course in OR, your brother can get into IT, Banking, Retail, Manufacturing, SCM etc. Knowledge of OR will come handy anywhere and everywhere. In India somehow OR techniques are not used widely.
Check what are his likes and dislikes and let him choose the right course. But then both the courses that you have mentioned in your post will under-utilise his talent and there will be no use of doing BSc (Stats).
If he is interested to join Navy what about Air Force. For flying pilot, earlier requirement was BSc (Maths/Stats). I don't know what is the current requirement.
All the best!
I agree on your response and infact its correct, there is no use of Bsc if he join to higher secondary course.
Well MBA is also in my mind, but now hopefully I will fix it and advice him to carry on MBA ops, and thats too make me think about Pilot course, you wake up me by giving hint..
Once again appreciate your advice.