The stimulus payment will go to the account you entered for direct deposit on the 2019 tax return. The direct deposit information cannot be changed. If the account is closed the IRS will send the payment by mail or on a debit card.
Go to this IRS website for stimulus information - https://www.irs.gov/newsroom/treasury-and-irs-begin-delivering-second-round-of-economic-impact-payme...
Go to this IRS website to check the status of your payment - https://www.irs.gov/coronavirus/get-my-payment
If you do not receive the second stimulus payment on or before January 15, 2021 and you are eligible it will be entered on your federal tax return, Form 1040 on Line 30.
The Form 1040 has not been finalized and needs to updated to include the 2nd Economic Impact Payment.