https://philosophybites.com/2008/09/adrian-moore-on.html
Philosophy Bites: Podcast on Kant's Metaphysics
In this interview with University of Oxford philosopher Adrian Moore, the fundaments of Kant's metaphysical philosophy are concisely and precisely summarized. (Moore also has a great interview on Kant's entire philosophical system in Five Books, in case a deeper dive is desired.)
https://plato.stanford.edu/entries/kant-metaphysics/
SEP: Kant's Critique of Metaphysics
This article from the Stanford University Encyclopedia of Philosophy comprehensively summarizes Kant's criticism of metaphysics in The Critique of Pure Reason and other works. This entry also summarizes...