Create your Google maps API key in:
https://console.cloud.google.com/apis/credentials
You will also need to enable Directions API:
https://console.cloud.google.com/google/maps-apis/api-list
After that, include the key in the Map widget and republish the application.
https://outsystemsui.outsystems.com/OutSystemsMapsSample/ShowDirectionsOnMap
Maps direction between two points A (your location) and B (destination).