As I don't live in Chennai, I have no idea. You will have to take some initiative to find suppliers. There are a list of Robot Shops at the bottom of the front page of this site (scroll all the way down). Take a look here to see if anything is helpful.
If you find additional suppliers local to you, please add them to the list to help others in your situation.
Truly, you will need to answer that for yourself after carefully reviewing the help people have been kind enough to post here. How can I tell you what you are capable of?
I can tell you that many people (including myself) have learned a great deal from this site and this community, but you have to be willing to do your own homework. There are many people building robots with no formal mechanical or electrical education.
People are willing to help you, but first you have to take advantage of the help that is already here in the form of documented Tips/Walkthroughs like the Start here robot from member Fritzl.
The first step is up to you. Good luck!
Please look at the "Start here" link on the top menu for this site. It gives you everything you need to get started.