Building new site while current site stays untouched online

L.S.

I just heard about the new Zoho Sites AI sitebuilder.

I want to use this new sitebuilder to update my current website. How do I go about that? Do I click "Create a new website"? Or do I start with the current website? It is important to me that the current website stays online until I am fully satisfied with the new design.

Also, any tips on AI prompts?

Thank you