Hi noreen-trinityth, thanks for joining the Community
To edit customer information in QuickBooks Online, navigate to the customers page and click the Edit button at the top of the screen beside New transaction.
If you don't see this option here, please try clearing the cache and cookies on your browser or sign into QuickBooks using a different web browser. QuickBooks uses cache and cookies to run faster, but sometimes these can also block pages from performing as expected. After clearing cache, make sure to restart your browser.