1. Installing Flutter
2. Updating Flutter path For Linux, For mac, For Windows.
3. Creating New App using terminal. Go to the directory where you want to save your project. Run below command in terminal/ cmd.

$ flutter create helloworld

4. Editing contents of lib/main.dart in helloworld project.

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Hello_World',
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        appBar: AppBar(
          title: Text('Welcome to Hello_World'),
        ),
        body: Center(
          child: Text('Her face a river. This is a curse, a blessing too.'),
        ),
      ),
    );
  }
}

5. Change directory to helloworld and Run your project

$ cd helloworld 
$ flutter run 

6. This will probably start App in browser. You can configure an emulator and run the app on it, or you may run the app on an Android or iOS smartphone.

• You can read about Flutter Introduction in details on provided links:

  • Get-started with Flutter on flutter.dev

  • Write your first Flutter app on flutter.dev