Google - Sir I want to open a store of mobiles. Where I can sell offline and online as well. So how?

There are many way to sell your mobiles online or offline, for offline you can tie up with some shop those are already selling, so they were sell your mobiles or you can open your own shop for offline selling.
For online shopping same thing you can do, there are many online firms like, infibeam.com, shopclue etc you can tie up with this firm where you can put you mobile here and it will sell easily or create your own website the start marketing , it will take time, i will suggest you tie up with some one like infibeam.