After you file

When you got to the screen shown in the screen shot below, did you select "Yes, I've already filed my return," and then "I need to amend my 2023 return"? If you selected those answers, Form 1040-X would have been created as soon as you clicked Continue. But when this screen first comes up, No is selected by default. If you clicked Continue without selecting Yes, TurboTax would then take you "through all the screens," which is what you said happened, and it would not create Form 1040-X. If you did not get this screen asking whether you already filed, then you did not follow the steps in the FAQ that I posted above.

At this point, do not try to fix the amended return that you started. Start over with the .tax2023 file from your original tax return. Carefully follow the steps in the FAQ, and read all the screens carefully.