-dev:
For parsing the GPS information, take a look at my NeoGPS library. It is smaller, faster, more reliable and more accurate than all other libraries, and the examples are properly structured. The library includes methods for calculating distance and bearing very accurately. Once you choose how to communicate between the rover and the "owner", you can send the target coordinates to the other platform (rover to owner, or owner to rover).NeoGPS is available from the Arduino IDE Library Manager, under the menu Sketch -> Include Library -> Manage Libraries.
Even if you don't use it, there is lots of information on the Installation and Troubleshooting pages. Be sure the read the section about choosing a serial port.
Thank you so much!