who are apple re-sellers, and what does it stand for. do they re sell used phones in india or i will get a brand new iPhone from them?

An Apple Authorized Reseller (AAR) is a business partner that has entered into a contractual relationship with Apple Computer Inc., to sell software and/or hardware products. The Apple website maintains lists of authorized corporate resellers and catalog/Internet resellers.

copied from http://searchitchannel.techtarget.com/definition/Apple-Authorized-Reseller-AAR

Apple authorised re-sellers can operate any way they chose in India ... and that also means they are not obliged to service Apple products, even for warranty purposes although many do. I understand that Apple are about to open their own stores in India and in my view you would be wise to await this. We read of many problems with re-sellers and a formal Apple store will uphold warranty and service obligations to the same standards as we have here in the West.

This is the Apple list of genuine resellers in India ,it is essential to establish from the list the products each one authorised by Apple to sell

https://locate.apple.com/in/en/