Finally !
https://www.macrumors.com/roundup/ios-13/
" ...
Major improvements to the Files app bring new capabilities to the iPhone and the iPad. For the first time, you can access files stored on a USB drive, SD card, SSD, hard drive, or SMB file server and there's a downloads folder in Files where you can manage all your web downloads and attachments from Safari and Mail.
Apple added a Column View to the Files app that lets you see details for your files as you browse, and there's now an option to share entire iCloud Drive folders.
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How to use External Storage with New iPadOS 13
https://www.youtube.com/watch?v=OJCSAGPhRw4