Unzip it using Unarchiver, as suggested by Microsoft. (With another tool you may get incorrect results.) If you download the VM in a ZIP file for VMWare, you should have three files.
Start Fusion.
Import the existing VM: navigate to the *.OVF file (one of the three in the unzipped folder).
In the running Windows 10 instance install:
MS Excel (You can use Office 2016, there is no need to register it.)