axdr
You will need to you use XAMPP or something similar. If not that, then you will need to use IIS. If you are not familiar with setting up a webserver on Windows, (typically Windows Server) then your best bet is XAMPP.
Google:
flarum iis
flarum windows
If I get some time, I'll try it out myself and create a tutorial for installing using Windows IIS, would also be pretty cool if you could use SQL SERVER instead of mysql, you know, to keep it in M$ family :p