How do I download the back up to another device

If the device is a new iPhone or iPad-

To set up iPhone from a backup, it depends on the method used. If you used iCloud, see here for instructions. If you used a Mac or PC (with iTunes), see here.

However, if you have your old device, Quick Start provides an easy way to transfer your data over. See here - Use Quick Start to transfer data to a new iPhone, iPad, or iPod touch - Apple Support

If the device is a Mac, see here for instructions to migrate data - Move your content to a new Mac - Apple Support

Hello kerry-ann256,

Congratulations on your new device! You just need to "restore" your iPhone so you can download your backup from iCloud onto your new device.

The instructions in this Support Article will help resolve your issue:

-> Restore your iPhone, iPad, or iPod touch from a backup - Apple Support