W3Schools Tryit Editor

main.jsx

index.html

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

function MyForm() {
  const [myCar, setMyCar] = useState("Volvo");

  const handleChange = (event) => {
    setMyCar(event.target.value)
  }

  return (
    <form>
      <select value={myCar} onChange={handleChange}>
        <option value="Ford">Ford</option>
        <option value="Volvo">Volvo</option>
        <option value="Fiat">Fiat</option>
      </select>
    </form>
  )
}

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

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