I'm trying to direct my URL to another website. When I attempt to add a domain that I already own, it won't accept it because of the .wordpress. I receive "Domain names can only contain letters, numbers, or hyphens."
A ".wordpress.com" site name is not a domain name. That is a subdomain of Wordpress. What is it exactly that you are trying to accomplish? What you were trying to do is point a Wordpress site name to a Homestead website, which cannot be done.