I don't have much to add, just want to second everything Noir_Desir has said, all really good stuff.
I'm not big on general rules in chess because each position is so specific, but I'm confident enough to say this one. Never play ...Nb6 (as black of course
) in the opening or early middlegame in the KID.
Also, as Noir mentioned, definitely worth trying to figure out why white has to play b3, and only then a3 and b4. That theme arises in other openings and positions and is a useful trick to know.
If you do get around to reading Zurich 1953, your KID will vastly improve, since Bronstein plays it several times himself as do many of the other players.