Hello there!
Greetings!
Civil service exams are not easy to crack considering the huge competition involved, but it not impossible to crack as well , you can clear civil services exam with right strategy, first of all start your preparation at least 9-12 months before the exam date. You should make a routine and study at least 8-10 hours a day. You need to complete your whole syllabus at least 1-1.5 months before the exam so that you can give for practising questions , you can go for following books to prepare :-
A Brief History of Modern India by Rajiv Ahir
Ancient India by RS Sharma
History of Medieval India by Satish Chandra
Art and Culture by Nitin Singhania
Certificate Physical and Human Geography
Maps Oxford School Atlas
India: Physical Environment (NCERT)
Fundamentals of Human Geography (NCERT)
Indian Economy by Ramesh Singh
Indian Polity by Laxmikanth
And once you complete your complete syllabus go through offline mock tests. Good luck for your preparation.
Thankyou
