Setting up an internation­alized app: the Flutter_localizations package

By default, Flutter only provides US English localizations.
To add support for other languages,
an application must specify additional MaterialApp (or CupertinoApp)
properties, and include a package called
flutter_localizations. As of January 2023,
this package supports 79 languages.

To begin, start by creating a new Flutter application
in a directory of your choice with the flutter create command.

flutter create <name_of_flutter_app>

To use flutter_localizations,
add the package as a dependency to your pubspec.yaml file, 
as well as the intl package:

flutter pub add flutter_localizations

-sdk

=flutter

flutter pub add intl:any

This results in a pubspec.yml with the following entries: