I moved to Nevada after the first of this year. It asks for my county of principal residence but only has CA. Will it let me go forward without it. Or Put CA residence?

That would seem to be correct -- it sounds like you're filing a California state return.

From what you're saying, it sounds like your state of residence at the end of last year (the year you're filing your tax return for) was California, and you moved to Nevada in 2024.

So, you'll be filing your California state tax return for last year, and the state portion of the TurboTax program (correctly) wants to know the California county you resided in last year.