Is there any online database that provides the firm level patent statistics of India for research purposes?
It is a little unclear what you are asking for, but I would like to recommend The Lens. This is an excellent site for searching for patents. You can easily limit to search to India and there is cool graphing of results. Here is one example of a search for patent documents in India using the search term "plant".
There are a lot of other things graphed as well. The Lens is free to use. If you create an account, you get some additional features like saved searches and collections, but you don't need to log in.