Typically when writing CSS, we will want to have it in a separate CSS file, so that we can easily reuse and update defined styles across different html pages from a central source.
This challenge is just asking for you to take the css you have written within the style tags, and rewrite it in the provided styles.css file.
In the code you shared above, your css file is blank. That is where you need to put your CSS rule
h1, h2, p {
text-align: center;
}
If you have tried copying and pasting the code from the style section from index.html file into the styles.css file and it did not work, please share the CSS so we can see what it looks like and can tell what is going wrong.