State

App.js

import React, { useState } from "react";

import Person from "./components/Person";

function App() {
  const [name, setName] = useState('');

  return (
    <div>
      <input type="text" value={name} onChange={e => setName(e.target.value)} />
      <Person name={name} />
    </div>
  );
}

export default App;