i downloaded it, but i dont know what app to open it with.
a puzzle game set in liminal locations, with procedurally generated rooms. · By
For the Future just use Chat GBT and ask him he will give u the Anwser. But for now, iam gonna tell u. You have to dowload a program that can extract Rar or Zip Data.
So if you click on the downloaded file, Windows asks you with what app you want to open it. Just go to the Microsoft Store and download this app. 
after downloading this app, open the file with this app and u can extract the folder and start the game.