Hi bobthegoatdude,
Thank you for using the Apple Support Communities! It's my understanding that you're seeking a way to back up your iCloud data. I can help.
Connecting a USB drive to your iPhone is not supported, however, you can connect one to a supported iPad model. You are then only able to access files stored on that external device via the Files app on iPad. iCloud data is not stored in the Files app. Learn more about connecting external devices with Files on iPad here: Connect external devices or servers with Files on iPad - Apple Support.
If you are looking for options to back up your iCloud data, check out this article: Archive or make copies of the information you store in iCloud - Apple Support. This article will walk you through how to create a copy of Contacts, and more.
Thank you for your post!
Take care.