Where is the slot to put my graphic card?

Go to that web site you give the link for, open the motherboard picture. See the horizontal slots on the lower left side, a long black one, two small black ones and a long white one? Your card will go in either the long black one or the white one. Don't forget when you are done and have your drivers installed to go to your BIOS and select the PCI graphics rather than the onboard.