W3Schools Tryit Editor

main.jsx

index.html

import { createRoot } from 'react-dom/client'

function Car(props) {
  return (
    <>
      {props.brand && <h1>My car is a {props.brand}</h1>}
    </>
  );
}

createRoot(document.getElementById('root')).render(
  <Car />
);

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