Learn HTML by Building a Cat Photo App - Step 1

Tell us what’s happening:
Describe your issue in detail here.

  **Your code so far**
<html>
<body>
  <CatPhotoApp>Hello World</CatPhotoApp>
</body>
</html>
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Challenge: Learn HTML by Building a Cat Photo App - Step 1

Link to the challenge:

Hi, welcome to the forum.
Please review this post which should help you with Step 1.