What do you mean by 'resolution' settings' or do you mean Screen settings.
The Tv will always automatically upscale any signal it receives to 4K, and I don't think you can change that.
If you mean the Screen settings this should be found by pressing the Settings button on the remote control,
select Settings on screen then go to Display and Sound and select Screen.
Here you can adjust the Aspect Ratio and viewable screen area if that is indeed what you meant.
