Allow me to clear things up for you.
Directly recording a deposit transaction isn't considered a sale in QuickBooks Online (QBO). It has to be linked to a sales transaction, such as a sales receipt or an invoice. It will be entered as an unapplied cash payment.
You can follow the steps provided by my peer, @JonpriL, to record sales transactions, as well as receiving the payment for these sale transactions. Additional details on this process for invoices can be found in this article: Record invoice payments in QuickBooks Online.
Once your sales transactions have been recorded, along with their respective payments, you can refer to this article on how you can match them to your bank feeds:
Lastly, to ensure that your QBO bank account matches the balance of your actual bank account, you'll want to do a reconciliation. Take a look at this article for the steps: Reconcile an account in QuickBooks Online. This includes a short video, as well as screenshots for your reference.
I'll be around in case you need further assistance. Feel free to drop a comment below, and I'll be sure to get back to you.