The Footer already has links to these pages so you should not need to change those, but you should complete the content of these pages.
Privacy Policy
In particular, the privacy policy is technically a requirement for almost every advertising platform, including Facebook. The page we've given you links to a boilerplate page which is not bad, but if you want our best recommendation, go to our good friends at https://www.freeprivacypolicy.com/ where you'll find not only the basics but also way more than you are likely to ever need!
About Us
People buy from people, not companies, and the move to online has actually intensified this trait rather than diminishing it. Don't tell your life story here, but at least provide some context for what your site is about, why it exists, and how you expect to help your visitor gain some benefit from not just pressing the back button.
Contact Us
This can be as simple as an email address, a form plugin that sends email, or a form that adds to your CRM. Your choice, but you should have something here as a sign that you can be trusted.