Yes, you can change the email and username on the account.
You would log in and go to Intuit Account. On a desktop/laptop, it's in the lower left corner. For phones and tablets, it's under the Menu icon in the top left.
On the Profile tab, you can change the email address and user ID to his. You will need your password to do each.
You may want to update the phone number on the account as well, as we often use it for security purposes. You'll find it on the Security tab.
