Q: Learning to use iCloud.

Hello nallgoat, 

Thanks for using Apple Support Communities. 

Based on your post, I see that you have enabled iCloud Drive on three Apple devices. After moving a file to iCloud Drive on your Mac, you can see the file on your iPad, but not your iPhone. I use iCloud Drive to store a lot of my documents. So, I know how important it is that you have access to them on all devices. I have a few things for you to try. 

First, use Get help using iCloud Drive, specifically, this section:

What if my files don't update to iCloud? 

Check these things first:

• Make sure that you have an active Internet connection on your Mac and on your iOS device.
• Sign in to iCloud on all of your devices, and turn on iCloud Drive.
• Install the latest versions of Pages, Numbers, and Keynote. See which versions of Pages, Numbers, and Keynote you can use with iCloud Drive.
• Make sure that you have enough iCloud storage. If you exceed your limit, you can upgrade your iCloud storage.
• Create a new document and save it to see if it uploads to iCloud. If it does, see if the other documents start uploading.

Next, on your iPhone, go to Settings > iCloud make sure that you are signed into iCloud with the same Apple ID as the iMac and iPad. If you are, go ahead and sign out of iCloud and sign back in. Then, check iCloud Drive on your iPhone for the file. 

And finally, give your iPhone a fresh restart and then check again. This article will help:

Restart your iPhone, iPad, or iPod touch

Have a great day!