Those percentages are IF you caught COVID in the first place. The odds of GETTING it in the first place for you is .01%. Compared to the flu, you are 40 times more likely to catch the flu during flu season than to catch COVID.
I wonder if the calculator assumes the same parameters when figuring your odds of getting the flu during flu season. My guess if you wear a mask, wash your hands and stay away from people, you won't be getting the flu either.