#1 → Run CMD (If you don't know where it is search it in your computer).

#2 → Write “ipconfig”,it will give you this(I censored my details) : ]

#3 → Copy your Default Gateway's IP and paste it to your browser,then write the following detailes Username : Admin / root / [root] / Administrator Password : admin OR Admin / root / [root] / Administrator this is what you will get(It will be designed different,if you have D-LINK it will be designed like mine)

#4 → Go to Advance > Port Forwarding / Find your Port forwarding in yours

#5 → This is what you will get

Press “Add” now.

#6 → Put it on Custom Service,then add your IP address (You can find it here : https://whatismyipaddress.com/)

#7 → Add the ports to your router Example :

External Port Start      External Port End      Protocol       Internal Port Start      Internal Port End                  7700                            7780                              TCP/UDP                         7700                                      7800

Picture for #6 & #7