If you want to avoid manually adding individuals to the Defend user group in Microsoft 365, groups can be added instead. 

To do this, follow the steps below:

1. Log in to Entra ID. 
2. Navigate to Identity > Groups > All groups > New groups. 
3. Under group type, select Microsoft 365. 
4. Under Membership Type, select Dynamic User. 
5. Select an Owner for the group. 
6. Select Add dynamic query.
7. Click Edit next to the Rule syntax box and paste in the expression below. Replace GroupObjectID with the objectID of the group to be added. 

Rule syntax:

user.memberof -any (group.objectId -in ["GroupObjectID1", "GroupObjectID2"])