They are almost unrelated, except for each having 4 wheels.
The biggest difference by far is that a kart has a solid rear axle. This means that a kart needs to become a 3-wheel vehicle in order to “turn in” to a corner.
That constant transitioning from 3 to 4 to 3 to 4 wheel vehicle is why karts have track-to-wheelbase ratio, caster, kingpin inclination, scrub radius, and many other things that are totally unrelated to automobiles.
PM