Please help me about dlink router :(?

Press the reset button for 10 seconds. The modem-router will have all default values restored. You will be able to access the modem-router by the LAN IP address of 192.168.1.1. Please note when your modem is used to connect a single computer to the internet it is a LAN - A Local Area Network. But once you use the router to connect another computer your set up is a WAN, a Wide Area Network which is a collection of LANs, may be 2 computers or 250 computers. So you will have to tick the WAN settings appropriately. In the figure provided by you all WAN settings are blank.