Ok, let me tell you something. First reset your router and also make your computer static ip address. Like if your friend has got an ip like this 192.168.1.1 then make your computer 192.168.1.230 manually. Then when you reset your router then also disable his DHCP and also make 192.168.1.25...
just but the telephone wire to modem and then configure it. Use the username and the password that your ISP gave it to then your internet will be live. There is no different every dsl modem will work any country. Good luck