Does a hard reset erase all data on iPhone 13+

What is your definition of a hard reset?

If you're talking about a forced restart, no it won't.

If you're asking about wiping the phone to start over, yes it will.

Force restart iPhone - Apple Support (IN)

What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

Do you mean a Forced Restart? A reset will erase a phone, but a Forced Restart will not. Exactly what are you trying to do on your iPhone?