How do I enter the “$8k Sr. deduction” on my state income taxes?

[xmasbaby0]

We cannot see your tax return and you have not told us what state you are asking about.   If there is an age-based deduction for being 65 or older for your state, it is most likely to be there automatically.  Your date of birth flowed from the federal return to your state return, so the software "knows" your age.   If you specify your state, someone may be able to help more.