Why are my Nikon D800 night photos kinda yellowish and orange?

I was taking some night photos in NYC last night and when I got home to look at them on my pc, all of the night photos were sort of yellowish and orange. The daytime photos are perfectly fine. Would someone with more experience tell me what setting I should be using for these night photos?

It's a white balance issue.

Best solution is to shoot in raw & then adjust WB in post.

You must adjust your White Balance settings.
At the moment, the camera is probably set for daytime/sunny pictures.
At night, you will need to set it to Tungsten or Fluorescent… Depending on the lighting.
Your User Manual tell tell you how to do that.

Each type of light source has a color temperature, which is in kelvin. Daylight is around 5,000 degrees kelving (5000K), while incandescent blubs are around 3000K which is why they give off a reddish toned light. Some lights like street lamps use sodium vapor which is a yellow/orange colored light and rather difficult to correct.
With that camera, you should be shooting in RAW. If your yellow night shots were saved as JPEGs then your stuck. RAW, however, allows you to change the color temperature regardless of what your camera was set at. For example, you could have set your camera while in RAW to incandescent and then shoot outdoors under daylight conditions. But because you shot in RAW, the color cast can fully corrected as if you shot the scene with the right settings. JPEGs don't save the image data the same way as RAW images do, so you're stuck with what you've got.
Get yourself a x-rite color checker passport so you can instantly color correct your images.