$ node -v
v14.15.1

$npm install --global yarn
/usr/local/bin/yarn -> /usr/local/lib/node_modules/yarn/bin/yarn.js
/usr/local/bin/yarnpkg -> /usr/local/lib/node_modules/yarn/bin/yarn.js
+ yarn@1.22.10
updated 1 package in 1.698s

$yarn --version
1.22.10

$yarn global add create-react-app

$npx create-react-app helloworld

success Uninstalled packages.
✨  Done in 46.14s.

Created git commit.

Success! Created amplifyapp at /Users/*******/helloworld
Inside that directory, you can run several commands:

  yarn start
    Starts the development server.

  yarn build
    Bundles the app into static files for production.

  yarn test
    Starts the test runner.

  yarn eject
    Removes this tool and copies build dependencies, configuration files
    and scripts into the app directory. If you do this, you can’t go back!

We suggest that you begin by typing:

  cd helloworld
  yarn start

Happy hacking!

$cd helloworld
$yarn start

import React from 'react';
import logo from './logo.svg';
import './App.css';

function App() {
  return (
    <div className="App">
      <header className="App-header">
        <img src={logo} className="App-logo" alt="logo" />
        <p>
          Edit <code>src/App.js</code> and save to reload.
        </p>
        <a
          className="App-link"
          href="https://reactjs.org"
          target="_blank"
          rel="noopener noreferrer"
        >
          Learn React
        </a>
      </header>
    </div>
  );
}

export default App;

import React from 'react';

const App = () => {
  return (
    <div>
      <h1>Hello World</h1>
    </div>
  );
}

export default App;