OneSignal ( Push Notification )

Login to Onesignal and create a project.

1. Give a name to the project
2. select default organization
3. Select android (FCM) and then click on next configure your platform

You will get this screen,

4. Integrate firebase in your project. Click Here

5. use the Cloud messaging API (Legacy) server key and sender ID

6. select Flutter as your target SDK and you will get your app ID.

Flutter Integration

1. Add onesignal_flutter to your pubspec.yaml file
2. Run flutter pub get
3. Now paste your one signal app Id