Hello all, Zodiac here. I've been struggling with finding a solution to this. I'm attempting to create an exact copy of a creation of mine while also keeping all layers for that project intact so that I don't have to create them all again. I've found that I can duplicate something and it keep the layers of the original, but what if I wanted to copy a creation and paste it into a new file, or have the software create new layers for the new copy? Are either of these possible?

The import command will do some of what you want, but although it will keep the groups separate the layer designation will be lost along with the layer name of course.
But all is really not lost! In the new objects dialog (latest versions of Inkscape only) you will find the groups still magically have retained their old names and now exist as groups in a larger group. Click on the Layer/group icon to the left of each name to promote the large group first (see** below) and then promote each group back to the original layers.

**You can leave the enclosing group for organizational purposes, renamed, to indicate the original file perhaps? But deleting it is easy; when you first import the file, position it and then hit ungroup. Your old layers are now the groups left, go into object dialog and promote them to layers. I recommend you don't do this though, the original group can keep those internal layers easily aligned for positioning, and if you are importing into a larger drawing it's easy to lose track.

I'm not entirely clear what you're asking. Is a "creation" a file, an image, a logo, an icon, an object, etc.?

If you're talking about a file, there's File menu > Save a Copy, which will save you a copy of the file, as it is at that moment (assuming you've Saved). Or else you could just copy the file in your file manager. Either of those will save the layer structure.