index-4a

HTML

<!DOCTYPE html>
<html lang="en">

  <head>
    <meta charset="UTF-8">
    <title>React</title>
  </head>

  <body>
    <div id="root"></div>
    <script crossorigin src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <script crossorigin src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
  </body>

</html>

Babel + JSX

class MyForm extends React.Component {
  render() {
    return (
      <form>
        <h1>Hello</h1>
        <p>Enter your name:</p>
        <input
          type="text"
        />
      </form>
    );
  }
}
const root = ReactDOM.createRoot(document.getElementById("root"));
root.render(<MyForm />);