The lesson let you pass, but that is the the correct way.
@quobogeba @brysonsnow1 I'm going to explain what you need to do in this lesson if you don't understand me drop a comment
In this lesson if you check your HTML tab you will see three tags (h1, h2, h3)
<h1>I'm going to be a serif font when I grow up!</h1>
<h2>I'm going to be a sans-serif font.</h2>
<h3>I'm going to be in cursive!</h3>
All three tags have no styling to it so we are going to add a font as well as a backup font.
Under the CSS tab we going to select each tag (separately) and add a font and backup font to each one.
This is the result you will see
The reason for having two or more fonts added which is backup fonts is: if the first font is not supported by the user it will take the second one ect.