@Summer-Lovlinger, osascript is only on Mac computers, so you'll need to find another solution.
I've found that I can make Spotify play/pause by pressing the spacebar, so a command like this works for me:
nircmd sendkeypress spcYou can download nircmd from here then run it and add it to your c:\windows folder so you can run it without specifying the full path.
You can find all of the Spotify hotkeys by pressing CTRL+/. I found that here.