Switching over my site to Upfront

Hi,

There was no option for Upfront on the dropdown for installed products so I just chose General.

Here's my question: I created our website (our main site) with Artisteer , which I never want to use again. The current theme we're using has an out of date JQuery version, so I have to do something about that. I would like to switch the site over to Upfront. Do I need to re-build the website again from scratch on a Staging platform with Upfront and one of the Upfront themes, or can I apply Upfront to the current website I already have up (on the Staging platform) and only have to tweak it?

How would this work?

Thanks,

Sherry