Accessing user input from a textarea element works the same way.

Code .value after accessing the textarea element.

<html>
<head><style>body {min-height: 300px;} input { font-size: 16px; } textarea { font-size: 16px; } </style></head>
<body>
  <h1>Customer Reviews</h1>
  <textarea id="reviewText" rows="5" cols="18" placeholder="Write your review here"></textarea>
  <br>

  <button onclick="addReview()">Add Review</button>
  <p id="addedReview"></p>
  
  <script>function addReview() {
var review = document.getElementById("reviewText").value;
var addedReview = document.getElementById("addedReview");
addedReview.innerHTML = review;
}</script>
</body>
</html>]]>

Make sure to code .value.