HOW DO I BACK UP MY APPS TO ICLOUD?

Apps are not backed up to iCloud. The data in the apps is backed up when you backup your device. If you restore from a backup, the apps will download again from the App Store (provided they are still available) and associated data will be returned.

Learn more about backup options.

Restore from backup: https://support.apple.com/en-us/HT204184

Also forgot to paste this after Learn more about backup options: https://support.apple.com/en-us/HT203977