Hi there, RovsterAJ.
The operating systems contain and manage all the programs and applications on your computer or device that enable it to run. That said, you'll have to put on the macOS before installing the QuickBooks Desktop for Mac.
Once done, you can install your QuickBooks file.
I've added these articles as your reference:
That should do it, RovsterAJ. Shoot a Reply if there's anything that I can help with the installation. Keep safe!