Thank you for contacting us, Ylice,
I'm here to help you today manage those deposits from 2018 and 2019 in the Make Deposit screen.
You're right that putting those deposits will change the balance on your accounts in QuickBooks Desktop. Those transactions in the Bank Deposit window are the payments posted in your Undeposited Funds account.
If your books have accurate records, I recommend consulting your accountant. He/She might have specific instructions on how to handle those deposits sitting on the Make Deposit window.
I've added the Record and make Bank Deposits in QuickBooks Desktop for additional information.
Should you need anything else, don't hesitate to leave a comment below. I'm always right here to help.