If a train is going around a curve is one track higher than the other (banked so to speak) or are they level???
On most (low speed lines), track is not banked or superelevated, and much of the freight lines is low speed (short lines, branch lines, secondaries, industrial track etc can be really slow - some excepted track has speed limits of 10 mph or less).
Anyway, faster mains do have superelevation - here’s a site with a little bit of info on that: