How do I block notifications from popping up on my screen when on certain apps?

[Mari-chan]

When I play some mobile games and need to see the full screen, sometimes my friend texts me or an app sends me a notification and it ruins my gameplay. Is there any way I can block notifications from coming on my screen when I'm on CERTAIN apps but not all? I'm using a Google Pixel XL and my Android version is 9.

 

[methodman89]

Open Settings, Apps, select the app you want, go to its notifications, change to a lower priority.

 

[SpookDroid]

This app can help, too (Samsung phones have this built-in).
https://www.xda-developers.com/gaming-mode-android-app/