If you go to the main page, https://majalis.itch.io/tales-of-androgyny you'll see a bunch of buttons about half way down the page that say "download". Find the correct version (PC, MAC, Android, etc) and download it. Assuming you're on PC (I don't know how MAC works, and I don't play on mobile) you'll then need to extract the file you downloaded (think of it like unpacking a box: all the stuff is in the file, but it's not "ready to use" in it's current state), if you don't know how to do that you can get a free program to do that here https://www.win-rar.com/start.html?&L=0
Once the file is downloaded and extracted somewhere (games folder, hidden porn folder, or just on your desktop for the brave!) open the folder, find the .exe file (it'll be called TalesOfAndrogyny and listed as an Executable Jar File in windows) and you can just double click that to run the game!