Android AWS SNS setting up

Copy your FCM project's API key

In the Firebase console, choose your project.

In the left navigation pane, choose the gear icon, and then choose Project settings.

Choose Cloud Messaging.

Under Project credentials, find the Server key. This your FCM project's API key. Copy it to your clipboard.

For more information, see Setting Up FCM/GCM for Push Notifications.

Create a platform application in Amazon SNS

Open the Amazon SNS console.

Open the left navigation pane, expand Mobile, and then choose Push notifications.

On the Mobile push notifications page, next to Platform applications, choose Create platform application.

On the Create platform application page, under Details, do the following:

Enter an Application name.

For Push notification platform, choose Firebase Cloud Messaging (FCM).

Under Firebase Cloud Messaging Credentials, paste the API key that you copied earlier.

(Optional) Set up event notifications and delivery status logging.

Choose Create platform application.

references:

https://aws.amazon.com/premiumsupport/knowledge-center/create-android-push-messaging-sns/