How do I add an additional email to my account to receive submissions

Do you want to add multiple email recipients to the Notification Email? If yes, I see that you are holding a Free account. Unfortunately, Free account is limited to only one email recipient on a Notification Email. If you want to add multiple email recipients you need to upgrade your account. For any paid account there is a limit of 10 email recipients on a Notification email and 3 email recipients on an Autoresponder.

You can check plans and pricing here: https://www.jotform.com/pricing/