const Example = () => {
  const [result, setResult] = React.useState('');

  return (
    <div>
      <Button
        onClick={() =>
          fetch('/hello')
            .then((res) => res.json())
            .then((data) => setResult(data.message))
        }
        variant="primary"
      >
        Fetch Data
      </Button>
      <div>
        Result:
        <output>{result}</output>
      </div>
    </div>
  );
};

render(<Example />);