How can I change the email address of someone who my form is being emailed to upon submission?

It's in the Settings > Email tab > Notification:

Please follow the steps on this guide: https://www.jotform.com/help/41-How-to-Find-and-Change-the-Email-Address-Used-for-Notification-Email. 

Hello-
I tried that but it says I need to upgrade in order to change or adjust the emails.
Thanks so much!
Always,
Lynn
...

We've implemented a limit of 1 recipient per email setting for free accounts. This follows after a series of abuse was detected on free accounts using this feature to send spam. I think creating a separate notification is still allowed. You may consider doing that if you want to send an email to a different recipient. 

Ok I will try that thank you!
Thanks so much!
Always,
Lynn
...