The Americas have a lot of different definitions. Here are some of the most commonly accepted/used grouping definitions,
presented with each country/territory sized as a function of its total population (c. 2020).

Programmed and rendered in MATLAB r2019b.

Here's a good Wikipedia rabbit hole starting point for the definitions:
https://en.wikipedia.org/wiki/Americas_(terminology)

Data source for population estimates:
https://www.statista.com/