Laura,

Unfortunately, if you do not have an archive backup, there is no easy way to get your project back.

To bring an existing webpage  into WebEasy the site must be imported. 

*Only sites built in HTML can be brought into WebEasy.

Try the following:

Save the existing site to your  local machine.
In WebEasy select File > Import HTML
Browse to the main page of the existing site and select 'open'Allow WebEasy to import the site

**NOTE** Once the site is imported often some editing is required to return the site to it's original appearance.  Importing is not a perfect process so this editing is normal before the  site  is ready to be posted using WebEasy.