In America, we often use the word good as a noun, sort of a shortened form of good deeds, good nature or good works. It is not an error to say, "He does a great deal of good in this neighborhood."
You are, of course, correct to say that that good is an adjective and well is an adverb, but sometimes these definitions can be transitory, which makes them difficult for non-native speakers to learn.
If she looks good(adjective), she's very attractive; if she looks well(adjective), she's no longer sick. She sees good(noun) in everyone she meets, even though she doesn't see well(adverb) at all without her glasses.