I need to enter $130 overpayment carryforward on line 37a of Maryland Form 502. This is overpayment of last year for 2023, NOT for 2024.Where can I input it in TurboTax?

Did you apply your 2023 Maryland refund to your 2024 Maryland tax return?   If so, and you used TurboTax last year, that amount should already be applied to your 2024 state return.   

If you did not use TurboTax and need to enter it, it gets entered in the Estimates section in the Deductions & Credits section.   Click Start or Update next to Other Income Taxes from the Estimates and Other Income Taxes Paid section.   From there, scroll down to 2023 Refund Applied to 2024.   And then select Start or Update next to 2023 refund applied to 2024 state taxes.   Then enter the amount.