Hello again, Maureen. Thanks for reaching back out for further clarification. I'll straighten this out. 

The Bank Feed is used to link your QuickBooks Online account to your online banking. The only way to attach an account to the Banking portal in QuickBooks Online is to sync it with a Financial Institution. You're still able to record cash transactions in your account, however this money will ultimately be 'deposited' into a bank account. If your accounts aren't connected to the Bank Feed, the account will simply appear in the register, or the Chart of Accounts. 

I hope this helps make sense of the Banking feature in the program. If you have any other questions, please don't hesitate to ask. 

Cheers!