Thanks for reaching out to us regarding your concern, Sallie. In QuickBooks Online, sharing the same email with users is not possible.
QBO requires unique email addresses for each user for security and privacy reasons. This ensures that each user has their own login credentials, and that data and communication cannot be accessed or shared by unauthorized parties.
I've included this article for detailed information on managing users in QBO: Add and manage users in QuickBooks Online.
Moreover, if you want to learn more about the different options for access permissions and user roles check this article: User roles and access rights in QBO.
I'm all ears if you need further assistance with managing users in QBO. Just add your reply below. Have a great day.