To select the most appropriate role you can refer to Azure roles in the Purview portal.
For example Compliance Data Administrator should help you to cover all aspect for Information protection.
Regarding type of file, not all can be natively covered by Microsoft services.
Create and configure sensitivity labels
MP3 and other binary files: Like music files, binary files do not support sensitivity labels natively. Labels can be applied using external tools or by containing the file in a labeled ZIP or other containers.
PDF files: Microsoft Information Protection (MIP) can apply labels to PDF files, and labels can either convert to an Adobe PDF label or be recognized by Adobe Acrobat if using the MIP plugin.
Image files (PNG, JPG, JPEG): These types of files do not natively support sensitivity labels, but labels can be applied via Azure Information Protection (AIP) or by using containers such as a labeled ZIP file.
Best regards,
Aleksandr
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