The General tab of your project settings should resemble
the following:

For a detailed overview of app signing, see
Create, export, and delete signing certificates.

Updating the app’s deployment version

If you changed Deployment Target in your Xcode project,
open ios/Flutter/AppframeworkInfo.plist in your Flutter app
and update the MinimumOSVersion value to match.

Add an app icon

When a new Flutter app is created, a placeholder icon set is created.
This step covers replacing these placeholder icons with your
app’s icons:

Review the iOS App Icon guidelines.

In the Xcode project navigator, select Assets.xcassets in the
Runner folder. Update the placeholder icons with your own app icons.

Verify the icon has been replaced by running your app using
flutter run.

Add a launch image

Similar to the app icon, you may also want to replace the placeholder launch image: