Hi tomb,
Thank you for taking the time to post your question to Apple Support Communities. We understand that your "iOS files" are taking up too much space on your MacBook Pro, and that you're looking for a solution to transfer them to iCloud.
To confirm, are the iOS files you're referring to backups of your devices? If so, we wouldn't recommend editing, relocating, renaming, or extracting content from these files, as these actions could potentially ruin them. Check out the "Find backups stored on your Mac or PC" section of this article for more details: Locate backups of your iPhone, iPad, and iPod touch
As an alternative, to conserve space on your MacBook Pro, you can back up your iOS devices to iCloud. How to back up your iPhone, iPad, and iPod touch with iCloud
If needed, the first link posted above provides steps to delete old backups on your Mac. We hope this helps.
Take care!