Does anybody know how I get the rest of my child tax from 2021 from January to June ?

[Critter-3]

First there were no advance payments from Jan to June ... only from July to Dec when 1/2 of the potential credit was sent out.  To get the other 1/2 you simply file a tax return and then  you are asked how much of the credit  you already got in advance and the rest will be a credit on line 28 of the form 1040 and will be part of the total refund. 

[xmasbaby0]

The advance child tax credit payments were sent from July 2021 to December 2021.   They were paid to you "in advance" as a credit on your 2021 tax return.    If you did not receive them then you can get the full amount of the CTC on your 2021 tax return.   If you received the payments of either $250 or $300 per child between July and December, you are required to enter that information when you prepare your 2021 tax return.  Letter 6419 was sent to EACH parent who received advance CTC payments so it is important to add all of it up to enter it correctly.

Federal>Deductions and Credits>You and Your Family>Child Tax Credit

The IRS is sending out letter 6419 to you.  It will show the amount of advance child tax credit that you received during 2021.  Enter the information from that letter carefully.   

The remaining amount of CTC that you can receive will show up on line 28 of your 2021 Form 1040.   Then it will calculate down to the refund you see on line 35a or the tax due on line 37.

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.

NOTE:   The CTC is indeed a “credit” that can be applied toward any tax liability that you would otherwise have to pay as “tax due”  to the IRS.