How do I import my Wix website in to an application?

My son has attempted to create an App using Wix and did the steps he watched from Google. It has built him a website that has a mobile view.

How can he import his website into a Wix App?

Is this a function you have to pay for? He has used the free web builder but if we need to pay we can

Please help. This is for a project he needs to deliver this evening.

Thank you in advance

this link may help you sort it out