Dear @Adz ,
Thank you for your post in our forum.
1.You are right, all files uploaded through SharePoint are saved in document libraries.
According to the tests, you could use /sites/{site-id}/drives
to get the drive ID, and then use /sites/{site-id}/drives/{drive-id}/root/children
to access the files in the library.
2.According to the research, there isn’t anywhere else to shore files except libraries.
Should you have any questions or concerns, please do feel free to contact me.
Yours sincerely,
Renjie Sun
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