I'll answer the first box for you, since I'm not sure about the other two. Who: It looks like the author of the passage, John O'Sullivan, was speaking about the people of America as a whole.
What: The author is discussing how America is a nation created by people from all over the world and many countries, but America is not very connected to the history of other countries. America is the country of freedom, equality, progress, democracy, and a bright future.
When: This was written about 55 years after America was finally freed from British rule, when America was still a very young country and its people were still working on creating the stepping stones of America.
Where: The passage discusses America, but does not specify where. Since this was written when about half the states were added, I think it walks about those already added states and possible states being added in the near future.
Hope this helps!