Hi @Joseph Wylie
You need to register your app to Azure AD, next grant Files.ReadWrite.All
application permission for this app and grant admin consent.
Since your working scenario has no UI view, then you need to use the unattended client credentials flow to obtain an access token.
After that, you will be able to use this token to get files hosted in OneDrive.
https://graph.microsoft.com/v1.0/drives/{drive id}/root/children
Hope this helps.
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