How to set Nikon d8 10 to take pictures on cloudy days?

If it's not manual control (don't take pictures manually). Just leave the camera settings to the camera management. You can use aperture priority. When the shutter is half pressed, the camera will give you the parameters you want. You can determine your own aperture by shooting the required depth of field. The shutter speed is given by the camera. If it is lower than the safety shutter, you can change the shutter speed by adjusting ISO.

Another problem is white balance. Automatic white balance can generally be used. If the hue seen from the viewfinder is abnormal, you can adjust or customize the white balance.