Hello Ankit Sharma,
The minimum qualification for taking the Civil service examination (IAS, IPS etc.,) is any degree. It can be either be literature or engineering. Since you are in first year of your degree you still have a lot of time to prepare completely for the exam.Let me give you step by step tips, so that it will be useful for you to make an initiation,
Thing You Should Know
Engineering doesn't have anything to do with your civil service examination.It is considered as a passport to take up the exam. A student with B.Sc or B.A or B.E or B.tech or MBA are all same and any one can take up the exam. It is also very clear than an engineering student can take any subject of his choise from the list of subjects immaterial of what is his major subject.That is engineering student can even take science or arts as his optional and a science or arts student can even take electrical or mechanical as his optional subject.So it's your choise to choose from the list of optionals.
Which Subject to Choose
Till last year the choise of choosing a subject in preliminary examination was given.From this year it will be two compulsory papers in preliminary examination, where you don't have option to choose.However the pattern of main examination will continue as like before, where you have to choose two optional subjects in which you have clear two papers in each.Talks are going on that even the main examination is going to be reformed too, but until a final news comes the pattern will continue.
Coming to your point, when you are choosing a optional you should be very clear about its merits and demerits also whether it is your subject of interest.When you decide to choose a engineering subject the first hurdle comes to you is , whether can you master it and even you are master in it, can you complete that paper in given time and whether the paper is of scoring type.
Let me give you an example, What is the capital of India? and the next question is Find the value of (a+b)^2 where a=87 and b=21.Both the questions are very easy and you are master in both. But when coming to answering and time management the first one is the easy one.This is the reason why most of teh people prefer arts subjects like Geography, Political Science, Public Administration or History.
My Suggestion to you
I will suggest you to prefer an arts subject like geography, public administration or political science and even Psychology.All the four are aspirants choise till day.History is also good, but the syllabus is vast and need continous revision.Though are new to these subjects, you can learn easily in the course of your study.I belong to science category and even I have choosen Geography and public administration as my choise.
How to start
Since you are first year of your college, you still have a lot of time.Concentrate on your academics and on preparation part be in touch with current affairs and aptitude questions as of now and then from your second year slowly srart teh basics off the optional you are going to choose.
Lot of books are available on the market.For general studies it is Tata Macgraw hill publication is worthy.
For complete details about the book list for various subjects and to have regular touch with weekly current affairs and hot topics discussed you can go to my blog, which I hope will be useful for you.
With Best Regards,