Hi. Today's game is a simple setup (no series of hoops to jump through) so the easiest method may be best (but bear in mind the easiest method is often not good enough). That being, let your browser "open" the zip file (a .zip file is a container for multiple files). Inside you'll see a setup .exe that you can double-click on to install the program. That's it.
If that should fail you could "save" the .zip file to a location on your drive, after which you can open it and run the setup as previously described. You can accept the default download location by clicking "save" (you'd have to know where that location is to get to your file) or you could right-click the download link to "save as" and then choose the location yourself.
As always, read and choose the installation options wisely.
Afterward you can run the installed program via the shortcuts it creates.
If you "saved" it then delete the .zip file when you're done.
There are lots of variables involved so offering foolproof help isn't practical without knowing how your pc is set up or what software you use. In this case I'm assuming zips will open easily for you and that you can handle the rest of it. Have fun!