If I am currently imployed, im not sure my actual start date (january 2021) on the state reviewit is asking my start and end data for employment during the tax year

If you were employed on January 1, 2023 in the state whose tax return you are working on, that would be the start date. The end date would be the last day you were employed in that state or December 31, 2023 if you were employed during the whole year.