title: How to push notification with Cloud Messaging Firebase from the server
body: <p>I already have an app and I want to start sending notification to the users. I already set up everything in the app(using react native) and I checked manually that I can send notification to the devices and it works.
  Now I want to run a job in the server who will push the message (with the device token) to the cloud messaging in firebase.
  I can't find a lot of details about how to do it. I would like if someone can give me any guide I can use with. my server is in Kotlin(java can be good too) and I m working with gradle.</p>
  
  <p>Thank you so much for the help </p>