I have the answer to my question using these links provided by a friend - in case anyone else has the same issue: https://learn.microsoft.com/en-us/windows-server/storage/disk-management/initialize-new-disks, https://learn.microsoft.com/en-us/troubleshoot/windows-server/backup-and-storage/troubleshoot-disk-management#disks-that-are-missing-or-not-initialized-plus-general-troubleshooting-steps, and https://learn.microsoft.com/en-us/troubleshoot/windows-server/backup-and-storage/troubleshoot-disk-management#open-disk-management