UPSC

BA means Bachelors in arts. Jobs opportunities after BA are:
Government entrance exams like SSC CGL, CDS, Bank PO position, jobs in BPO, UPSC examination, etc.

Yes. But, you should know English and one Indian language as they are compulsory papers.

If you have a graduation degree, that would be enough for you.

Do your graduation and take coaching classes along with it.

Law, ethics, Geography, history, political Science, environment, Current affairs, aptitude and logical reasoning English and Indian language.
Read papers Regularly.

Sociology, syllabus and easily available but if you have command over your graduation subject then I prefer you to go for that. For getting good marks you need to prepare hard for one year atleast and also you can go for coaching. It's the toughest Indian exams for most intellectual minds.

IAS IFS and IPS are the most demanded services so those services are given to top 50-70 rank holders and for SC, ST top 22.

English and Indian language exams are must for UPSC exams.

No. Any one Indian language and English.

Just be an avid reader of "The Hindu"
3 years before you plan to give exams start coaching. Choose your optional subject B4 hand so that you don't have to mug up just before the exam. If you are going to give exam next year, then you should start right now. Join coaching but if you can study by yourself, go to market and but books and give time to every subjects.