How to 'SAVE AS' an existing project?

I am not an experienced FCP x user and am looking for some assistance,
A few months ago I took a time lapse photo session and imported the images into FCP and had a 3 second display time associated with the images. I posted it on YouTube.
Now I reduced the time to 2 seconds for each frame to shorten the film but do not see how to 'save as' this film so not to over write the existing film. I want to have both videos on YT just make the longer one private.
Ideally I would like to keep it in the same folder with the other assets.
How can I best accomplish this?
Thanks in advance for your help!
Rich

If you're using the Share to YouTube setting, the simplest way is to duplicate the project with a different name. The export will use the project name. Perhaps I'm misunderstanding the problem.

Tom
I was using share to export to file. After reading your reply I looked at the export dialogue and noticed the save as ability exists there and not in the top menu bar.
So I now understand how to do it.
I was looking at the FILE cmnd and did not see the save as option vs looking at the share cmnd hence my question. I have not used this program in several months.
Thanks for your help.