Can't find FS2020.exe!

Yes. Apps bought from the Store (same for many UWP apps) are stored in a folder that is invisible and initially not accessible to the user.
It is located in “Program Files / WindowsApps”, the latest folder being invisible.

Access to this folder is limited to the TrustedInstaller. If you REALLY need to go there, you can by changing the rights. I suggest you don’t go there if you don’t know what you’re doing.