Go to the notifications button in the menu bar, or the Notifications section itself.
Here you can edit your preferences, such as the frequency with which you receive the notifications.
To remove the feature from an item, identify it on the list and click the "X" on the right side.
By confirming this action, you will no longer receive alerts on this content.
You can also do this directly in the content by selecting the "Active Notifications" button again.