What you are looking for is a render scale option. It is usually specified as a percentage of your display resolution but could also be combined with upscaling (DLSS, FSR, XeSS, etc.) options.
It's something that is up to the game developer to implement but it is becoming more and more common to see in games now.
It's something that is up to the game developer to implement but it is becoming more and more common to see in games now.