Do I enter 1500 for my spouse and I if we received 3000 advance child tax credit

That is what you enter. 

The "refund monitor" starts off by giving your all of the stimulus money and all of the child tax credit because the software does not know yet that you received stimulus money or that you received some advance child tax credit payments.    That gets reconciled later.

That "refund monitor" changes as you enter information.      That is normal.   And you cannot take it seriously until you enter ALL of your information---even though it is so tempting to believe that the highest amount is the "right" refund.

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.

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.