Storage
How do I download my storage from another device to this device
iPhone 7, iOS 12
Question marked as
I don’t understand your question. You cannot download storage to another device. If you want to used iCloud storage for multiple devices, you are free to do so as long as you are signed into the same Apple ID and iCloud account on those devices and as long as you have space available.
If you mean how do you transfer what you have in iCloud to another iOS device, you restore the backup. You can read about it here.
https://support.apple.com/kb/PH12521?locale=en_US