You will find the BuddyBoss Notifications settings on your WordPress admin area navigating to the GamiPress menu -> Settings -> Add-ons tab.
From these settings you are able to configure or disable the notifications of all elements. In case you wish to configure or disable notifications for a specific points type, achievement type or rank type then you need to modify the settings of each type.
Tags allows you to place dynamic text to personalize the notification content in the way you wish. The add-on comes with different tags to place information about the user (first and last names and included the user ID for shortcodes) and about the element earned (title, link, thumbnail, etc).
To see the tags available you need to look at bottom of each notification content input where you will find a link as shown in this screenshot: