U Got Router Yes? Follow Instructions
1. Open you browser.
2. Enter you Router Ip (Dont know open Cmd and enter Ipconfig)
3. Enter password (If you don't know ask your parents maybe it's admin/administator sometimes)
5. Go to tools > Miscellaneous > Enable UpnP > Restart Router.
6. Can't find tools then search in your'e router for UpnP
This is a option to open your NAT Settings.