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I don't know about a Korean phone's software. It could be out of sync with a US version for several reasons, including region-dependent features (though these typically favour Korea when they exist), being based on a different SoC, or if it was a network-specific handset you may need to use that network's SIM to see updates (many US carrier handsets behave that way).
You could work around the raw+jpeg thing by using a third party app like Open Camera. That gives raw+jpeg on my Pixel, whose own camera app doesn't offer that (probably because it relies on computational photography and hence there won't be a single raw image).
On a side note, the core of the OS is called the "kernel", after the core of a seed (or of an idea), rather than being named after a military rank (it took me a few seconds to work out what you meant there ).