Civil Servant (IAS/PCS) exams

1. You should concentrate on current affairs and general knowledge.
2. You can read NCERT books of history, geography and polity.
3. You can prepare from UPSC books.

The age limit for all candidates irrespective of their gender is
21-32 years.
You can appear for UPSC if you come under this age limit.
But as you are from general category, you will have only 4 attempts to give UPSC.

Yes, it is possible. Sri Chaitanya and Narayana IAS academies are giving coaching for students who have done their 10th. But, I would advise you to not to take that. Concentrate on your 10th board exams and on your 12th. You can start taking coaching after 12th. For now, just read the newspapers.

You are eligible to appear for Civil Services Examination conducted by UPSC after BBA from a recognised university.

Yes, you need a degree to appear for the exams you have mentioned. That degree maybe B.Tech, B.Pharma or any other.

Hi,
First and foremost thing, read the newspaper daily. I suggest you Hindu for that. Keep good memory of current affairs. You must know some important aspects of the constitution. Then choose a good coaching institute and work hard.

Maximum age to appear for civil services examination for general category candidates is 32 years with 6 chances as maximum. If you have not availed your chances yet then you are eligible to appear for civil services examination.

Rau's IAS UPSC Coaching in Delhi is a known institute. Other known institutes are Made Easy and Career Launcher.
Check below link for more -
https://testprep.shiksha.com/government-exams-in-india-categorypage-14-54-1-0-0-1-1-2-none-1-0

You are eligible to appear for civil services examination conducted by UPSC after completing B.Sc CS to become Indian Foreign Service Officer. You are not eligible for Indian Forest Service, unless you have cleared with one of the subjects named animal husbandry, physics, statistics and zoology, agriculture, forestry, engineering, etc.

Bajiram and Ravi is the best.