How can I generate voice navigation for turn-by-turn directions for Google Maps on my laptop?
As Mapperz mentioned, it is not available. However, an option would be to use Bluestacks Android Emulator. (We are using windows 10 Home Edition).
I do not have a BT GPS to test it out with Bluestacks if you want to do the turn by turn live, however you can see the directions if you want to.
The Windows Store probably has some apps you could use instead of installing Android Bluestacks.
We offer a WPF Windows Desktop app that offers Turn by Turn Directions (offline disconnected optionally available if you load data) http://mapdiscovery.techmaven.net