“Each .nav-link element should link to a corresponding element on the landing page (has an href with a value of another element’s id. e.g. #footer).”
You have three nav links:
<li><a class='nav-link' href='#features'>Features</a></li>
<li><a class='nav-link' href='#how it works'>How it works </a></li>
<li><a class='nav-link' href='#pricing '>Pricing</a></li>
Where are the corresponding elements they link to?
Your product landing page should have a section for Features, a section for How it works and a section for Pricing. These internal nav link should link to those sections so that when the user clicks on a nav link the page jumps to the relevant section.