It’s good to see you in the Community, @chapin123. I have the steps you need to upload bank statements in QuickBooks Online (QBO).
QuickBooks now offers a convenient feature that enables you to access your bank statements directly from some banks. This feature comes in handy, particularly when you need to reconcile accounts for multiple clients or several statements for one account. Here's the list of the banks that support this feature.
After that, you can follow these steps to manually attach the bank statement: