When looking at the new cars, what codes do you mean? Provide an example please. If the code is a string of numbers, it is probably a code used by your dealer. If you are talking LX, S, EX, etc., those are the trim levels and can be looked up. Most model codes in ads are not relevant to the car's model or trim level but to the dealer's inventory. Let us know what you are looking at though.
Welcome! Like you, I have been searching for a (first) new Soul. When I look at one local dealer's listings, I see:
Body Style: Hatchback
Model Code: B2532
I presume this is what you mean? Unfortunately, I cannot decode them for you. It would appear they denote broad categories of vehicles, roughly corresponding to the trim levels. Model Code: B2532 seems to be the 2020 Soul S trim. I suspect they are more useful to the computerized inventory system than to human beings. Sorry I don't have a real answer for you other than assuring you you're not crazy. Happy Soul hunting!