I was developing a small project ( app for Android) in Cordova ( https://cordova.apache.org ), and this project one of the requirements was to send notifications push ( push notifications ) to the application through the Service Cloud Messaging Google Firebase ( https://console.firebase.google.com ).
The procedure for implementing this task is relatively simple. Just access the Google Firebase console, create a new project, enter the information (name, package, etc …), configure it for Android and finally download the file google-services.json