Government & Defence Entrance Exam

There is no such pre-defined subject combination for B.A. Which can be said best for IAS. But, if you have History, Geography, Economics, English, Public Administration ( any two or three from these 6 subjects ), it would be more helpful in IAS preparation. For IAS. It is better to have one language subject and anyone or two subjects from History, Geography, and Economics. Best wishes.

Along with the job, it will take time to prepare for IAS. You can take the help of a coaching institute/ experienced person for preparation along with the regular self-study of 3-4 hr for 1-2 year. It is about time management as many IIM passes out have cracked IAS along with job.

No, female and unmarried candidates are not eligible for NDA.

For appearing in NDA, you need to be in at least class 12th as the minimum age required is 16.

Do a lot of hard work and pre for civil services exams.

No, you can't. You need to be in class 12th or passed out, because the age criteria is 16 years minimum.