transfer data one iPhone to another

You backup the first phone, and restore the second phone to that backup. See this support document for further assistance. Transfer content from an iPhone, iPad, or iPod touch to a new device - Apple Support

You need to explain what you are trying to do in more detail. Did you get a new phone? Are you trying to send data to another person?

Transfer content from an iPhone, iPad, or iPod touch to a new device - Apple Support

You can't.

Data and files of both devices should be synced and imported to your computer, then both devices can sync to that same data.