Changing the front page of a site (that was made without WP)

Hey, I have a new site that I just changed the frontpage of using dreamweaver, but I decided I would just get WordPress to build the site.

But, when I edit the ‘About’ page, which links to the frontpage of the site, nothing changes and it just displays the old frontpage.

Do I need to delete the hosted files associated with the current frontpage before I can start editing the page in WP?

This is the site if anyone is curious: https://historytidbits.com/