W3Schools Tryit Editor

main.jsx

index.html

import React from "react";
import ReactDOM from "react-dom/client";

function Hello(props) {
  return <h1>Hello World!</h1>;
}

const container = document.getElementById('root');
const root = ReactDOM.createRoot(container);
root.render(<Hello />);

/*
The examples in this tutorial are created using the
create-react-app.

Install the create-react-app,
and you will be able to run the same examples on your computer.

In this example we create a component called 'Hello'.
The component is rendered in a container called 'root'.
*/

<!doctype html>
<html lang="en">
  <body>
    <div id="root"></div>
    <script type="module" src="/src/main.jsx"></script>
  </body>
</html>