Spray crete

it coated with a spray coat product. I live in the Chicago area and am worried about winter damage to the coating.All comments will be appreciated.

Don't even think about such a band-aid approach. Your patio looks bad now because it was a poor job in the first place. Find a reputable concrete contractor that does small jobs, have the present patio jackhammered up and hauled away and then put down a proper tamped base and pea gravel drainage. With fiber reinforced concrete and some mesh/ rebar, topped off with a sealer you should be good for several decades even in Chicago. HTH

Joe