Are you asking for UPSC? You can prefer any of the coaching material given below
ALS IAS Academy Delhi
Chanakya IAS Academy Delhi
Elite Academy Mumbai
Rau's IAS Study Circle Delhi, Jaipur, Bangalore etc.
Here are some preparation tips you can follow for the exam preparation:
Go through the previous question papers : Go through with previous year papers as it will give you an idea about the exam.
Make your own notes : It is always advisable to make notes of the related topics as you go through the books and other study material. A well drafted note solves two purposes.
Strategy for General Studies: General studies paper is equally important for Prelims and Mains examination.
History : It is a huge section & Also emphasis is given to Ancient India. A cursory glance over the medieval history is also necessary.
Geography: In this there are physical geography and maps related questions. So get yourself well-acquainted with maps with the help of a good Atlas.
General Science : It covers a major chunk of this paper and a standard guidebook can make you well-versed on the topics of general science.
Current affairs : Going through a standard newspaper daily can keep you updated on the current affairs topics.