Where on the Turbotax forms do I enter the 1099-DIV box 12 amount and where do I enter the portion of that amount that is from my state of California?

You will enter your Form 1099-DIV into TurboTax and then answer the follow-up questions about your form to properly enter it for your state and federal tax return.

You can enter your Form 1099-DIV into TurboTax as follows:

1. Click on "Search" at the upper right of your screen.
2. Enter "1099-DIV"
3. Select "Jump to 1099-div"
4. Answer "Yes" to "Did you have investment income in 2024?"
5. Select "Skip Import" on the screen that asks "Let Us Enter Your Bank and Brokerage Tax Documents"
6. Select the box that says "Dividends 1099-Div" (the box will turn green with a checkmark on it)
7. And "Continue"
8. Enter your 1099-DIV information and select "Continue"
9. Answer the follow-up screens about your dividend interest
    

You will see a separate question to determine how your Box 12 dividends are taxed by your state. State's tax Federal obligations differently.

That is addressed on the screen, "Tell us more about your exempt-interest dividends."  When you enter your Form 1099-Div into TurboTax pay close attention to all prompts and questions, especially as they pertain to your state, You will use the drop down box to select your state and then "Continue".

Click here for "Where Do I Enter Form 1099-DIV in TurboTax Online?"

Click here for "What is IRS Form 1099-DIV"

In your original question you asked "where do I enter the portion of that amount that is from my state of California?"  According to the California FTB "California does not tax dividends paid by a fund attributable to interest received from U.S. obligations or California state or municipal obligations IF at least 50% of the fund's assets would be exempt from California tax when held by an individual.

It looks like you reported exempt interest dividend from a fund with more than 50% of assets that are California exempt, and should not be added back to your CA income.