If you mean changing your email address in your new QuickBooks Self-Employed account, you can access accounts.intuit.com to see the associated email like your QuickBooks account. In the Email address section, select Edit and change your email. From there, you can also use a different user ID or remove the old one.
Another option is to fill out an email change request. Once approved, you'll receive an email from firstname.lastname@example.org with the next steps and instructions on what to do next.
To learn more about managing transactions within your book, you can visit these articles: