@Edward Jones, Thanks for posting in Q&A. In fact, when assign Intune license to a group, it will assign the licenses to the members in the group. That is to say, if we have 5 users in this group, 5 available Intune licenses are needed to be available in our tenant. If not, it will fail with error.
https://learn.microsoft.com/en-us/azure/active-directory/enterprise-users/licensing-groups-assign
Hope the above information can help.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.