Web push with firebase and Angular fire

I to all. I am a programmer and i need help to configure the push notifications on a web app developed with angula angular Fire and Cordova. I installed angular Fire but when i try to get the token i recive errors on the console log because the service worker isnt registered even troough i put the firebase-messaging-sw on the root of my server application.
I am a programmer and i will pay only for a working solution