Graphic card is a part of computer , Is you have graphic card (Check it )

Graphic card (GPU) is a hardware component which is physically connect with motherboard 

Role of graphic card 

It is use for playing games in good quality ,seeing videos, photo and video editing application.
In short graphics card control the display pixel density and processing on image.

Check is graphic card is available in your computer or not-:

Right click on my computer and select manage after that open Device manager then select Display adapter.
There You can check which type of graphic card in your computer

Graphic card increase your gaming experience