For 2023 taxes...4th Qtr payment due 15 Jan?
Either
1) print that out from your 2023 PDF tax file (should be in there....you do have that PDF?)
2) get a paper copy directly form the IRS (print it out) (lower down on this page for the 2024 1040ES PDF forms..at least right now)
Forms & instructions | Internal Revenue Service
or
3) Go to the IRS payment site (Direct Pay) and just pay it Online...make sure you select 2024 as the tax year.
Payments | Internal Revenue Service