The phenomenon that human beings know is actually not the way things are, because the phenomenon has been processed by subjective conditions. Kant is in an era of constant debate between rationalism and empiricism. He thinks both views have shortcomings. He accepted that knowledge must come from empirical judgment, but he also affirmed human rational reasoning ability.
Kant believes that the key to the problem lies in knowing the subject; To ask what people know, it is better to ask what people can know first. Knowledge is mastered by people through three abilities: perceptual ability receives various phenomena of things through the stimulation of external things, intellectuality is the material provided by using concepts to master sensibility, and rationality is the logical thinking by using reasoning.
I suggest you read Kant's Critique of Pure Reason, not the next reader.
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