For flashing your phone you will need to collect or download come important things.
- Download the firmware of your phone
- Put it in one specific folder
- Install flashing tools or box setup which you want to use as a flasher
- Download and install USB driver of your phone
- Take a backup of your important data
- Connect your phone with PC via USB data cable
Download links
Samsung Galaxy Grand 2 (G-7102) Firmware Download