Generally, does "Native Americans" consist of all the Indian people in both North and South America?

The term "Native American" can refer to the indigenous population of any part of the continents of North or South America. Usually, however, it is taken to mean specifically those of North America (America and Canada). In that case it replaces the term "Indians" or "Red Indians", a term which was used because, briefly, the discovery of the continent of America - but more particularly the discovery of the Caribbean islands - was confused with a westward journey to the easternmost islands of Asia, which were called 'the East Indes' - "Indian" being the correct adjective relating to both "India" and "the Indes". When referring to the aboriginal population of Central or South America, it is best to avoid confusion either by using the name of a specific group ("the Aztecs", "the Mayans") or by using the name of the country ("the indigenous population of Chile") or, in general, by specifying the continent ("aboriginal/indigenous population/people of South America." It should be noted that, especially in British and Australian literature, the term "Aboriginal" is often used to mean "the aboriginal/indigenous people of Australia". Especially when shortened to "Abo", it has become nearly as derogatory a term as the 'N' word (used for people of African origin). As you can see from this Wikipedia article, the use of the terms "Native American", "indigenous American", "Amerindian" and so on are very far from being clear cut, even today: