[jyl]

You have to install Windows, it is easiest if you have the ISO file. Parallels creates a virtual PC inside MacOS, you run Windows on that virtual machine, and run your Windows application in that instance of Windows. Install Parallels Tools as well (it's pretty automatic), then choose Coherence mode and your Windows application will look and act like it is running natively in Mac OS. Windows and Mac applications can use the same clipboard, access the same drives and files. It will be a little confusing at first but not for long.

I run MS Office 365 for Windows in Parallels, that is by choice, I prefer it to the Office for Mac, and Parallels makes it easy. I also think Windows 10 is very good, so no reason to use Windows 7 or Vista or the misbegotten 8. I actually like the Edge browser and if I weren't so lazy I'd switch to Outlook for email.

Parallels 12 costs about $100, Windows 10 a little less. Parallels + Windows consume about 1-2 GB of RAM.