Transfer photos from old usb stick to my iPad Pro 2nd generation

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Connect external storage devices to iPad - Apple Support

Direct import of photos and videos from your camera SD Card to your Photo library is possible - subject to a couple of caveats:

• the SD Card must be correctly formatted as FAT, FAT32 or exFAT (FAT64)
• stored photos are stored within the expected DCIM folder

Import photos using Apple camera adapters - Apple Support

If you are unable to use the direct photo import feature, you can still manually access and copy photos from the SD Card using the iPad’s built-in Files App. To do so, just open the Files App - and in the Sidebar you will see your SD Card in the list of Locations. If necessary, open the sidebar by tapping the sidebar icon at top-left of the Files App Window. Photos can be copied to the iPad Photo Library, or copied to a folder of your choice either on your iPad or elsewhere.

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Import photos using Apple camera adapters - Apple Support

Import and export photos and videos on iPad - Apple Support

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ipad import photos from sd card - Google-