Answer

WMV (Windows Media Video) files use proprietary Microsoft codes, which do not work with the Apple operating system.  

But do not despair! There are free alternative media players that play WMV files that you can download on your Mac.

The most popular one is VLC Media Player: "VLC is a free and open source cross-platform multimedia player and framework that plays most multimedia files as well as DVDs, Audio CDs, VCDs, and various streaming protocols."

Apple has some services that can convert a WAV file to a compatible format for Macs and iPhones such as  the Apple music app and iTunes.

For additional options, see the Top 5 Free WMV Players for Mac Options or How to Watch WMV Files on Mac.