Can the back up be encrypted? I’m trying to install Norton-Lifelock and it requires me to encrypt my backups.

Encrypt your backups

On a Mac with macOS Mojave 10.14 or earlier, or on a PC, open iTunes. Connect your device to your computer with the included USB cable. Then locate your device on your computer. From the General tab or the Summary tab, select "Encrypt local backup" under the Backups section.

About encrypted backups on your iPhone, iPad, or iPod touch ...

Avoid anything by Norton on your computer. It's not necessary and Norton also has a long history of messing up Macs.

LifeLock also has a long history of exposing customer data. They are preying on your fears to sell you a service you probably don't need.

Effective defenses against malware and ot… - Apple Community

https://krebsonsecurity.com/2018/07/lifelock-bug-exposed-millions-of-customer-email-addresses/