The reason you can't find invoices under Create or Customers is that under Create, you can only create invoices, and on the Customers page, you can only view your customers' details.
To successfully navigate your created invoices. Please refer to these steps:
Sign in to your QuickBooks Online account.
Go to the All apps menu.
Click the dropdown arrow beside Sales & Get Paid and choose Invoices.
From there, you can locate your created invoices.
Moreover, did you know that we provide a complimentary session with our QuickBooks Live Expert Assisted service? Our experts excel at making financial management effortless and offer tailored advice, especially in managing your sales.
If you need further assistance, please return to this forum. I'm always here to help.
I wanted to follow up on your concern and see if the solution I provided has resolved your issue. Please let us know if everything is now working as expected or if you have any questions. We’re happy to assist you further.