Contents:

The battery is in the trunk under the compartment cover.
When replacing the battery, disconnect the negative (-) cable (1) and remove the positive (+) battery fuse box (2).
Remove the battery mounting bracket (3).
WARNING - Touching metal surfaces in the trunk under the compartment cover

Do not touch metal surfaces in the trunk under the compartment cover while the engine is operating or hot. Doing so could result in serious personal injury. Turn the engine off and wait until it cools down or wear gloves to replace the battery from the luggage room.
Your vehicle has a maintenance-free, calcium-based battery.
When recharging the battery, observe the following precautions:
Reset items
Items should be reset after the battery has been discharged or the battery has been disconnected.
Kia Stinger (CK) 2018-2023 Owner's Manual: Mode Control Actuator
Description and operation Description Located in the heater unit, the mode control actuator adjusts the position of the mode door by operating the mode control actuator according to the signal from the A/C control unit. Pressing the mode select switch shifts the mode control actuator in the order of Vent → Bi-Level → Floor → Mix.Repair procedures Refilling And Bleeding Never remove the radiator cap when the engine is hot. Serious scalding could be caused by hot fluid under high pressure escaping from the radiator. When pouring engine coolant, be sure to shut the relay box lid and not to let coolant spill on the electrical parts or the paint.