I am from USA and I have no idea about the hearing aid center in Chennai, you just do a Google search which will help you to find out the hearing aid center.
If you're still searching, it can be daunting at times, which is why there are a lot of free online resources that tell you what you might have to expect at your first hearing test, including this super useful website! I hope it helps, and I hope you find an audiologist close to your area!!