2023 instructions for Form 1040 U.S. Individual Income Tax Return, Schedule 1 (Form 1040) Additional Income and Adjustments to Income, Schedule 2 (Form 1040) Additional Taxes, and Schedule 3 (Form 1040) Additional Credits and Payments can be found in the IRS Instructions for Form 1040 and 1040-SR.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.