Government & Defence Entrance Exam

Hello,
For IBPS PO preparation, 3 to 6 months are enough. You can easily prepare for the exam in the given time. But, it will be good to start preparation from now. Whenever you get time, solve previous year question papers. Stay updated with all the latest news and current affairs. You should try to make your basics of mathematics strong.
Time management is the most important thing. So, you have to solve questions in minimum time.
You can visit the below mentioned link:
https://ask.shiksha.com/which-short-term-course-should-i-pursue-to-get-a-good-job-in-the-private-banking-sector-qna-3881640
I hope it helps.

IAS surely means brilliance in your academic career. You should try for a distinction in your BA. It will become a good launching for you. IAS implies every day work. So, nothing is wasted.

You have to show a consistent academic performance for a good future. You have to get a first class throughout your career. So, work for it now. You need to take care of your academics. There is no separate preparation for IAS.

Indian army does not have any weapon designing cell. Indian army weapon designing needs are fulfilled by DRDO. You can join DRDO on completion of B.Tech mechanical engineering. DRDO trains its engineers in weapon designing. You can also join Defence Institute of Advanced Technology - Pune for M.Tech with specialisation in weapon and armaments design.

You can not appear for any exam as the minimum qualification for it is a graduation in any stream. It is suggested that you must first complete your graduation. Along with it, you may prepare for different banks exams. All the best.