Does free version shows Ad aside the “Created in Editor X”
Until you purchase a subscription, you can not apply a domain name to the site nor remove then Wix X banner. Once your site has been completed, you can purchase hosting and direct the domain to the new site, disassociating it from the Wordpress site you have set-up.
Not sure what you mean by link menus, but all menu directories either point to an external website URL, page within the site, document hosted at the site, email or phone number.
I hope this answers your question.
Correction on the buttons found in the navigation, they only link to pages, and external URLS. And you are welcome! Good luck.