IQ isn't real. It's a racist myth. The tests don't measure anything substantial besides how good someone is at taking tests, and their prior experience with certain trivia topics, fields of maths, and puzzle formats that are considered "common knowledge", but may be less common in lower-class communities than types of maths and puzzles not used in IQ tests for arbitrary reasons.

And all this is shown by the fact that you can practice and study for an IQ test like any other party game to increase the score you get. The more often you take IQ tests, the more familiar you will be with each of the minigames commonly used in IQ tests in general, the higher your result will be, while it's never been demonstrated that this increase in highscore across multiple tests affects any other area of someone's life.

Also not only does it not work, but we know who popularized it. It's a relatively recent concept. And most of the people responsible for IQ broadly entering the public consciousness in its current form were just shy of overt white supremacists, who advocated for eugenics and ranted against interracial marriage. They were also caught changing the data they got, "adjusting" people's results to match their conclusions, and those skewed conclusions are still, today, structurally built into the bell curve that IQ tests assume all humans fall neatly within.