td;lr - If you are trying to look for the Roblox Game App on the Mac App Store, you may not find it.
If you have an Apple Silicon M1/M2-based ARM-based Mac/Macbook, you can install native iPhone and iPad apps on your Mac, condition - the app is made available by the developers for Mac computers. Sadly, Roblox is not available under "iPhone or iPad Apps" tabs as well.
When you visit the Mac App Store from your Mac device web browser, you will see a message "This app is available only on the App Store for iPhone and iPad."
Follow this article to offially install Roblox Game App on Mac computer - https://code2care.org/howto/install-roblox-game-on-m1-m2-mac-intel-m1-m2