RoboHelp 7 HTML - Begin a new project based on existing one

Hi there.  I'm a tech novice, looking to create a NEW help file for a different software program of ours based on an EXISTING RH7 file we have.  I need to leave the old one as is, as that will continue to evolve and be further edited, need both to run parallel now.  This new one would be based on the existing file, but with new tweaks and features.  Looking for the best way to do this.

I found an old post that read this:  'Copy project folder itself, then open and rename it in RH. This should leave the original project and an exact copy with a new name.', and the moderator felt this was the right solution.

However, that doesn't leave me comfortable enough with what I need to do.  Can anyone expand a bit more?  Ex; What is that folder I need to copy, where is it?  I expect the folder that has the same name as my project and is in here: C:\Program Files\RoboHelp Office\RoboHTML, but then where should I put it after I copy it, same folder?  I guess I'd make sure that new folder has the name of the new project I'd want?  How do I get to it from RH, is that just the 'Open' folder I see under my existing projects on the main RH screen?  Apologies for the novice speak, I'm just most terrified of ruining my existing file, that would be horrible.

Years ago I created a new project from our even older one and imported topics one by one - that took forever.  Don't want to do that again if I can avoid it.

Thanks!

Amanda