Questions about example sentences with, and the definition and usage of "Queens"

A: Queens is a borough in New York.

The neighborhood called Flushing has mostly Chinese and Korean people. Corona heights has mostly Central and South Americans.

"Each home to people..." means that each neighborhood is a home to certain people. It is saying that similar people call that place their home.

A: as a native English, I can honestly say I have no idea what the creator of that shirt was trying to say, lol

A: "Queens Boulevard" is the name of a certain street, the sentence "Queens Boulevard is really busy," means that this particular street has a lot of traffic, or is crowded

A: "Queens building is just PAST that as you head north." It would mean you would see that building as you head north (indicating you know which way that is!)