every I see a mainsteam media portrayal of a “foreigner” in America, its never a White or Black person

That has not been my experience, I think you may have confirmation bias, but it depends so strongly on the particulars, and I'm only making this narrow point here. Like Marvel movies, to name a specific set of examples, has white+black+Asian-looking people from Europe, white from Scandinavia and Russia, black from Africa and India, and so on. Even much older movies like Coming to America with Eddie Murphy featured several black men and women ostensibly from Africa - so saying "never" is far too strong there. Though as for how "common" it is... that I don't know, and maybe you are only looking at a particular genre, and only at movies from the last year or five or some such, and perhaps it is true in that more limited sense.

On the other hand, we see Asian-Indian people like Aziz Ansari and Hispanic people like Gabriel Iglesias speaking English, and white people such as Arnold Schwarzenegger who infamously arrived here from another country (Austria in his case), and black people similarly such as Idris Elba and Sidney Poitier. Though definitely Asian (and Indian) representation has lagged behind non-white, since the days of Leave It To Beaver started off television. And comedians are one thing while movies are another - Hispanic people who speak English are definitely underrepresented (but still not "never", like The Mandalorian). George Takei (Sulu) famously appeared alongside Nichelle Nichols (Uhurha) and Walter Koenig (Checkov) in the original Star Trek series from the 60s - but nowadays the most Asian-American actor might be Steven Yeun (e.g. The Walking Dead) or John Cho.

So you definitely have a point, I just wanted to nit-pick some of the particulars in how you said it: "never" is a very strong word. Also, does Hollywood really "engrain" these ideas onto the population, or merely reflect the pre-existing biases back at us? Yes! As in, it does both, creating a feed-forward cycle that would require effort to overcome.