can I create a backup on an external hard drive rather than the cloud?

getAppleHelp wrote:

I want to be able to backup my iPhone, iPad and MacBook Pro to an external hard drive. Is this possible?

—Back up your Mac with Time Machine: https://support.apple.com/en-us/HT201250

3-2-1 Backup Strategy: three copies of your data, two different methods, and one offsite.

How to create a boot clone https://discussions.apple.com/docs/DOC-10081

Use external storage devices with Mac

https://support.apple.com/guide/mac-help/use-external-storage-devices-with-mac-mchl027f1d66/mac

The iDevices can be backed up on the Mac—

Back up iPhone - Apple Support

https://support.apple.com › guide › iphone › ios

Back up iPhone using iCloud or your computer. If you replace your iPhone, you can use the backup to transfer your information to the new device.

I don't know about the iPad or iPhone but you can not back up your Mac to iCloud. You use an esternal drive to back up your mac. See: Back up your Mac with Time Machine - Apple Support