Can't use Move or Copy. Export needs Upgrade.
What you want to do isn't possible. iOS doesn't have a usable file system with folders, etc. Apple has restrictions in place to prevent that.
You can mark files in Dropbox as available offline, so you have access to them even when you're not conencted to the Internet, or you can export files to other applications, but it's not possible to export files to a folder on the iPad.
can files be exported to Windows 10 ?
Simply not true for newer Ipads. Other apps already allow the transfer of files between server and the IOS/iPadOS file system. Get facts straight and update your app to support this feature.