As I mentioned in my response to your other question, there are many things to consider when taking data offline. What extent do you need (sounds like you want all of India, but often you only need areas where there is no network coverage for accessing services), what zoom levels do you need (it seems you want all zoom levels), and which basemap (Imagery? Streets?).
For your requirements, just downloading the basemap from a service will not be practical, and may not even be possible (a basemap for all of India with full zoom levels will result in a very large file). But there are other ways to get this data, like with a product such as StreetMap Premium.
I would suggest you contact your local Esri distributor to discuss options. If you're in India, that would be Esri India: https://www.esri.in/ They will be able to help you determine the best approach for your application, and provide the support you need to implement your solution.