How do you change you notifications email?

Follow the link for changing your Apple ID email address. Apple basically uses one email address for pretty much everything except as outlined in the link I provided earlier.

"Apple ID email address

When you create an Apple ID,

you enter an email address. This email address is your Apple ID and the

username that you use to sign in to Apple services like Apple Music and

iCloud. It's also the contact email address for your account. Be sure

to check your inbox regularly. We'll send you email notifications to

help you manage your account."

Change your Apple ID - Apple Support

Normally, messages from Apple are sent to your Apple ID email address. There isn't a way to change that. If you want them sent to a different email address, you would need to change your Apple ID email address.

About your Apple ID email addresses (was "Manage your Apple ID primary, rescue, alternate, and notification email addresses") --> About your Apple ID email addresses - Apple Support