You get the EIC on your tax return. You don't apply for it separately. When your prepare your tax return, first enter all of your personal information, including dependents, and enter all of your income. Then type EIC in the Search box and click the link that says "Jump to eic." TurboTax will ask a few questions to determine whether you are eligible for the EIC. If you are eligible it will include the EIC in your tax return.
If you are eligible for EIC it is added to line 27 of your Form 1040 automatically if you have entered the income you earned from working and your dependents (if you have any dependents.)
https://www.irs.gov/credits-deductions/individuals/earned-income-tax-credit/use-the-eitc-assistant
Look at your 2023 Form 1040 to see the child-related credits you received
PREVIEW 1040
https://ttlc.intuit.com/questions/1901539-how-do-i-preview-my-turbotax-online-return-before-filing
Child Tax Credit line 19
Credit for Other Dependents line 19
Earned Income Credit line 27
Additional Child Tax Credit line 28
You do not have to do anything to "apply" for EIC. If you are eligible, TurboTax (TT) will give it to you automatically.
If you think TT missed it (unlikely), enter at:
Federal Taxes Tab (Personal for H&B version)
Deductions & Credits
-Scroll down to:
-You and your family
--Earned Income Credit