.env guide

1. add package flutter_dotenv to the project. - https://pub.dev/packages/flutter_dotenv
2. add the .env to the assets within the pubspec.yml
3. add *.env to the .gitignore
4. add the import import 'package:flutter_dotenv/flutter_dotenv.dart'; to the main.dart file and use await dotenv.load(fileName: ".env"); to load the .env file and make sure that the .env file is not empty.
5. If it was empty or haven't been created at the time it was added to the pubspec.yml go to pubspec.yml again and press ctrl + save
6. import the package wherever necessary import 'package:flutter_dotenv/flutter_dotenv.dart'; and use dotenv.env['VAR_NAME']; the VAR_NAME should be the same as the one you want to load from the .env file.