You can update the phone using the iTunes application that can be downloaded from the official website or through the OTA (Over The Air). To update it through OTA, make sure the battery is charged to 85 % or more and there is an active Internet connection while you are connected to a WiFi network. On phone go to Settings > General > Software Update. Unfortunately, it's not possible to add Persian language because this is specified to a certain area. If you are in Europe, Persian language won't be available. This is available only in certain areas.