You can edit a device group to: add to the group; remove firewalls from the group; update friendly name and tags.
To edit a device group
The Root Group cannot be edited.
Make changes to the Friendly Name and Tags fields, if needed.
To move devices from one device group to another, first you need to delete the devices from one group and then add them to the other group from Unassigned Firewalls list.
When you add a device to a group that already has a template applied to it, the template configuration is made available to the newly added device and therefore you need to commit and deploy the available updates on to the device.
Click Save.