Translation:Doctor Wang is American.
I think on its own it means "person" but in can also be applied to a country name to mean a person of that nationality.
美国 = America 美国人 = American
That would probably be something like "王是美国医生." Your sentence makes sense, but not as a translation of this Chinese sentence.
Not necessarily. Nationalities can be used as adjectives or nouns, so "Doctor Wang is an American" treats "American" as a noun (American person) while "Doctor Wang is American" treats it like an adjective (from America). Both are right.
Can anyone hear 不是 instead of 是? Can anyone kindly explain why the audio sounds wrong to me?
Why you said US american ? US means united state , but if you want to say a person of that country so you said just : american :)
"US American" is a very clunky phrase, and almost never used. In most of the world, except perhaps in Spain and South America, "America" in most contexts will be understood to mean “the United States of America", with very little chance of legitimate confusion.