Scope controls the URL structure that encompasses all the entry and exit points
The Start URL is required and tells the browser where your application should start when it is launched Start URL prevents the app from starting on whatever page the user was on when they added your app to their home screen. Your Start URL should direct the user straight into your app, rather than a product landing page. Think about what the user will want to do once they open your app, and place them there.
Additionally, you can add query parameters to start url to control the pwa visits, as seen below, ?utm_source=pwa
By using query parameters, you can control more things when a visitor comes through the application.