Preparing for a new school odyssey

The ending of a “2001: A Space Odyssey” is one of the most confusing moments of film I have ever seen.
Yes, I have read through countless articles and have read and understood the theory that the whole movie is about the evolution of man, and I do in fact agree with that. However, when first watching the movie it is almost impossible to understand what that gigantic black rectangular prism is, and how it functions in the movie.
I skimmed through one article that stated it was some alien invention that pushed a species to evolve. That is why the surrounding apes are able to use tools, while others cannot. That is then paralleled through Hal, the computer who later attempts to kill everyone. As Hal, the computer, is being destroyed he begins to feel himself dying, which establishes that we do not know in fact if Hal is truly alive or dead.
Afterwards Dave, the protagonist and lead scientist, travels through space and evolves through outside forces. The box reappears and then suddenly he is transformed into some sort of fetus with the face of a man. This all relates to high school, in some sense.
As I am a senior at Lawrence Woodmere Academy, who is almost done applying to college, I can completely relate to the movie as a whole, and as my sister is a LWA freshman, I can see the arc of her development.
I see the whole spectrum; from her biology class to my organic and biochemistry class, I understand how she is almost primal man and how I am Dave at his deathbed waiting to become the “star child.”
At her point in her life, she is completely new to the high school environment, the classes are more difficult and all of a sudden she is responsible for herself. Yet, she does not yet know Advanced Placement classes so; she is not a full human yet, on the evolutionary scale. Whereas, I am at the end of the journey having taken AP classes, honors classes, and a whole slew of others. I feel like Dave preparing for his new journey.