my advice would be to seek out a tax pro the first year. they could give you tips to save taxes and could point out things you not doing correctly which can cause serious tax and other problems both for the current year and in the future.
examples:
for a 2020 calendar year S-corp, the return is due 3/15/2021 but can be extended.
some states tax the income others do not
did you take a salary?
did you pay for health insurance that you want to deduct as self-employed health insurance? there are certain tax rules that must be followed otherwise you get no deduction.
maybe your state requires the S-Corp to carry workmen's compensation insurance even if you are the only employee. failure would result in big fines.
did you incur start-up costs? there are certain tax rules for deducting them.
if the S-Corp has a loss do you have enough basis to deduct it on your 1040?
