You'll have to ask your employer. You can probably leave it blank. Other than a federal deduction (box 19), for those who itemize, TurboTax usually does nothing with it.
TurboTax can only do a very few city returns. For a list of cities that TurboTax (TT) can handle, see: https://ttlc.intuit.com/questions/1899325-which-city-income-tax-returns-can-turbotax-handle. TT can do Ohio School District Income tax (SDIT) too.
