Hi there, @sallie.
You can add the transaction that you manually input like an invoice, expenses, then match the transaction. I'll show you how to do it.
Once done, the transaction is assigned to all of the categories you specified, saved to your register, and moved from the For Review tab to the In QuickBooks tab.
For more reference, you can read this article: Assign, categorize, edit, and add your downloaded banking transactions.
Also, for future reference, on how to categorize downloads you can read this article: Match and categorize your downloaded bank transactions.
If you have any other concerns, don't hesitate to let us know. Have a good day!