You can inactivate the bank account in the Chart of Accounts and create a new one. I'll show you how.
Then, create a new bank account once done.
If your bank account is set up to Bank Feeds, make sure to disconnect the online connection before inactivating it. Then, connect it to QuickBooks Online (QBO).
I've added a link that you can read and learn how to review bank transactions after you download them into QBO: Match and categorise bank transactions in QuickBooks Online.
Let us know if you need anything moving forward. We're here to help.