You say no when asked if you received advance child tax credit and if it asks if you got letter 6419 you say no.
Make sure you have entered your child as a dependent in My Info, and that you have entered the child's Social Security number. If your child was born in 2021make sure you said he lived with you the whole year. There is an oddly worded question that asks if the child paid over half their own support. Say NO to that question.
The software will automatically add your Child Tax Credit to line 28 of your Form 1040.
PREVIEW 1040
https://ttlc.intuit.com/questions/1901539-how-do-i-preview-my-turbotax-online-return-before-filing
Click on Tax Tools on the left side of the screen. Click on Tools. Click on View Tax Summary. Click on Preview my 1040 on the left side of the screen.