Add a textarea.

src/App.tsx

@@ -1,23 +1,13 @@
 import React from 'react';
 import logo from './logo.svg';
 import './App.css';
+import Editor from './Editor';
 
 function App() {
   return (
     <div className="App">
       <header className="App-header">
-        <img src={logo} className="App-logo" alt="logo" />
-        <p>
-          Edit <code>src/App.tsx</code> and save to reload.
-        </p>
-        <a
-          className="App-link"
-          href="https://reactjs.org"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          Learn React
-        </a>
+        <Editor />
       </header>
     </div>
   );

src/Editor.tsx

@@ -0,0 +1,11 @@
+function Editor() {
+  function handleChange(event: React.ChangeEvent<HTMLTextAreaElement>) {
+    console.log(event.target.value);
+  }
+
+  return (
+    <textarea onChange={handleChange}></textarea>
+  );
+}
+
+export default Editor;