Flight Simulator - Game Pass won't find the game to install

Hello Afruzu how are you?

My name is Ezequiel I'm an Independent Consultant.

What appears when you try to connect your internet on your Xbox? Are there any error codes or warnings?

Yes you can play this game offline, however you need to download content from it so you can play offline.

1-Open "My Games & Apps" on the Xbox console by choosing the "My Games & Apps" tile on the Xbox Dashboard or by opening the Xbox Guide and choosing the "My Games & Apps" option.
2-Find Microsoft Flight Simulator in the "Games" section of "My Games & Apps". Note: If you are installing or pre-installing Microsoft Flight Simulator, the game will immediately appear in the "Games" section and you can do this during installation.
3-Open the Microsoft Flight Simulator "More Options" menu by highlighting Microsoft Flight Simulator under "My Games & Apps" and pressing the "Menu" button on your Xbox controller.
4-In the Microsoft Flight Simulator "More options" menu, navigate to the "Manage games and add-ons" option and open it.
5-On the Microsoft Flight Simulator "Manage Games and Add-ons" screen, highlight and open "Microsoft Flight Simulator" on the right side of the screen.
In the "Microsoft Flight Simulator" menu, navigate to and select the "Manage installation to (storage device)" option.
7-On the Microsoft Flight Simulator "Manage Installation" screen, navigate to the "World - offline mode" add-on in the Microsoft Flight Simulator base game. Note: Selecting the "World - Offline Mode" add-on will install it, while unchecking it will either uninstall the add-on or prevent it from being installed.
8-After making the changes, navigate and select the "Save Changes" option on the right side of the screen.
9-Your Xbox will automatically update the Microsoft Flight Simulator installation in the background.

https://www.windowscentral.com/microsoft-flight-simulator-xbox-offline-mode-pack

This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.'12

Microsoft Flight Simulator Available August 18, 2020 with Xbox Game Pass for PC (Beta)

Check this page if you want to pre-order.

I have the xbox game pass and I found that I just had to uninstall and reinstall the xbox app(had already installed the 90 gb the previous night). Then run the app the first time, log in and then close the app. Restart the app and it should detect your
flight simulator install. Running the flight simulator from the newly installed xbox app seems to get me through the infinite "press a key" loop.

I'm actually kinda curious if the flight simulator is going to be on game pass now.

Cloud gaming is currently only for console games. Flight Simulator is currently not available on console, so won't be on cloud either.