Hello, so you need to download the windows folder, then you need to unzip it with a software (I personally use Izarc it's free and it does the job, but there is a lot of different software.) You will then get a folder, open it and you will find the .exe to launch the game right away!
If you don't want to bother with those extra step, we are also on steam where you just need to click to download and the play button, steam will launch the game automatically^^
I hope it helps! If you have more question, don't hesitate!