Firebase Cloud Messaging service provides the Push Notifications support inside of your application. More details here: https://firebase.google.com/products/cloud-messaging
You can use the same one for Push notifications or for Firebase Deep Links.
Ensure Firebase Cloud Messaging API (V1) is enabled
In your project, click the Gear icon next to "Project Overview" in the top left of the left-hand menu and select Project settings. Select the Cloud Messaging tab.
If Firebase Cloud Messaging API (V1) is disabled, then click the kebab menu icon on the top right corner and open the link.
On the subsequent page, click Enable. You may need to wait a few minutes for the action to propagate to Firebase systems.
You can skip this step if you have already set up the Notifications feature.
(Only for iOS) Ensure the "Push Notification" capabilities are enabled for your App.
Please use the following guide to generate the authentication key is you do not already have one.
Inside your project in the Firebase console, select the gear icon, select Project Settings, and then select the Cloud Messaging tab.
In APNs authentication key under iOS app configuration, click the Upload button.
Browse to the location where you saved your key, select it, and click Open. Add the key ID for the key and click Upload.
Enable Firebase Push notifications on the Natively platform
Turn the switcher on
Upload the iOS Config file (GoogleService-Info.plist)
Upload the Android Config file (google-services.json)
Click the 'Save' button to save your changes
If you have already enabled the Firebase Deep Links feature for your app, you may see the iOS Config file and the Android Config file uploaded. That's because these files are the same for the Firebase Notifications feature.