SimpleHook.jsx

const Hello = () => {
  const [number, updateNumber] = React.useState(0);
  return (
    <div>
      <p>{number}</p>
      <button onClick={(prevNum) => updateNumber(prevNum + 1)}>Add 1</button>
      <button onClick={(prevNum) => updateNumber(prevNum - 1)}>Remove 1</button>
    </div>
  )
}