You only need to enter the percentage from your state. The rest will be exempt from federal but taxable to your state.
On the screen Which state are your $XXX.XX of exempt interest-dividends from? Check I earned tax-exempt dividends in more than one state.
In the dropdown, select your state and enter an amount. For example if you had $100 in exempt-interest dividends and your sheet says 10% exempt in your state, enter $10 (10% x $100). On the next line, enter More than One State (the last choice in the dropdown). Enter the rest of your exempt-interest dividends. For example, if $10 was exempt in your state, enter $90 in More than One State ($100 - $10 you put for your state).