The NY Form IT 196 isn't ready for filing yet. It's scheduled to be available on 1/24/2019.
When it is ready, you first need to make sure that you have entered all of your potential itemized deductions in the Federal section of the program. Then, when you start the New York portion of the program TurboTax will automatically calculate whether you are able to itemize for NY separately from the federal standard deduction. If so, the Form IT 196 will be used for your NY state taxes.
