https://www.rtings.com/tv/reviews/lg/cx-oled/settings
Follow this, not sure how familiar you are with tv settings in general. For whatever reason most tvs out of the box have this ridiculous soap opera/motion blur setting enabled. The cx is probably one of the few TVs that are almost set perfectly out of the box.
If you play on any console make sure the input is set to game mode (found in picture setting) with deep color (found in general settings).
Also, whenever you play a game in HDR you'll want to adjust picture settings again (game mode hdr) as they are different than non hdr game mode settings. Like previously stated the colors are mostly on point, just need to adjust enhancements like motion blur and other settings in there.