Of the 16GB of video RAM that shipped with your card, 8GB is reserved for graphics processing, and the remaining 8GB is available to your computer for other uses, if needed.
Your computer has no video RAM, which means it's using your graphics card only. Either you have no integrated graphics, which is not typical these days, or your integrated graphics is disabled in the UEFI (which it should be.)
If you are running two monitors, you could use your graphics card to drive one of the monitors, and your integrated graphics to drive the other. This would require additional software to manage.
Other information in the image you supplied:
Your nVidia graphics card has its own BIOS. The BIOS version is 90.6.44.809b. Today's graphics cards are more like small computers.
Your DAC (digital-to-analog converter) is integrated in the card, and the conversion is performed in the card's own memory, which is why it's called a RAMDAC.