"In 1984, George Orwell proves that through surveillance, manipulation of language, and the prohibition of individuality, a totalitarian government can gain complete control over its citizens."
College English teacher here. That’s a pretty typical example of the way my good students write essays when they arrive, and I can see it getting an “A” in high school. But there are still a lot of ways it could be better.
For example, the thesis (quoted above) is a three-subject “list” thesis that anticipates the subjects of the three body paragraphs: one on surveillance, and one on manipulation of language, and one on prohibition of individuality. That’s a real “high school Harry” move that plays well on AP tests, but would have your college teachers slapping a “C” on your paper in two seconds. If they were to see this paper in draft, they'd ask you to write a more complex, interpretive thesis that makes a single claim that you then develop in detail in body paragraphs. One way they might do this to ask you to write on one of your three subjects at length, rather than superficially on all three. Another way is that they'd dig into your body paragraphs and find your best idea and ask you to revise the essay to make it your thesis, and then explain, analyze, and develop it at length.
Also, I’d like to see your Works Cited and would definitely run your paper through a plagiarism checker. Yours are some pretty well-known interpretations of 1984, and though they might be new to you, your teacher has probably read about them 100s of times before and is saving his or her “A”s for something that stands out with more interpretive flair.
I hope this helps, and good luck.