This requires some effort. You will need to call a service that does the route-planning for you. Like routelogic.io, myrouteonline.com, or any other. Create the api-consumption module for it, and setup your app to add the route-points.
For showing the stops on the Google Maps widget:
Add the maps-widget to your page and feed this widget a set of data-points in its property 'Objects' on tab 'Data source'. And set the lat- and long- attributes:
That will give you: