Thanks for coming to the Community for help, @susan26.
Adding a new bank account in QuickBooks is quick and easy. I'm here to help show you how:
If you need to inactivate or delete your old account, you can refer to this article for more information: How to delete an account or restore a deleted account.
Let me also include this related article if you need to connect bank and credit cards in QuickBooks: How to Connect Bank and Credit Cards.
That should do it. I'm here to help if you have additional questions about adding and deleting accounts. Have a good one.