Adding Sat Nav to a car with no Sat Nav

[Highwire]

Im thinking about changing the radio unit screen, and at the minute it doesnt have Sat Nav.

 

If change the radio unit screen to one that has the NAV button, does Sat Nav automatically come with it, or do I have to do something else?

 

 

[Simon TDI Sport]

Got to change the unit in the globe box aswell. That's the "brain" if you like. Do you not have AA or carplay.