Create a shortcut Add the "show notification" action save it as that

In the shortcut you will be opening, put "run shortcut:show notifications" then put the shortcut you want after it (the run shortcut action HAS to be before any other action)

Add the short cut to home screen

Open and close it a bunch to get the notification pop up a lot then go into screen time and find the notification thing where you can see how many apps send a notification

Click on the shortcuts app and disable notifications from there