If you have configured users and tags you can configure "groups" of users to be a recipient of alerts. This will save you from having to manually add users to alert configs - especially useful if you often add and remove users.
Set up a tag and add users
Follow the separate guide on setting up a tag and adding users to it.
Configure tags as an alert recipient
When configuring an alert you'll be able to specify a tag to receive alerts.
Note - it's not possible to configure a group alert to have a tag as a recipient - only individual services or devices.