The a (anchor) element is used to link content outside of your web page.
a elements need a destination web address called an href attribute as well as anchor text.
Final Code
<h2>CatPhotoApp</h2><main><ahref=https://www.freecatphotoapp.com>cat photos</a><imgsrc="https://www.bit.ly/fcc-relaxing-cat"alt="A cute orange cat lying on its back."><p>Kitty ipsum dolor sit amet, shed everywhere...</p><p>Purr jump eat the grass rip the couch scratched sunbathe...</p></main>