If you're receiving more notifications than you wish to see in your device, these can all be controlled in your Apple device's own dedicated Notification Center.
If you'd like to turn off all notifications at once, perhaps at night or when you don't want to be disturbed, just swipe up from the bottom to show your settings buttons and tap the 'Do not disturb' moon-symbol, this will allow notifications to be delivered, but they won't make any sound or wake up the screen display.
If you'd like to tweak the settings for do not disturb, go to your Settings > Do Not Disturb settings. You can do things like set a schedule for the Do Not Disturb to be active.
Tap your settings button and then tap 'Notifications'. You'll see all your apps listed there and you can switch them off and on, change how they display, etc. so it can all be tweaked to your own preference.
A full guide to using the Apple notification center can be found by tapping here
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