I am going to have a test on this Friday, however I cant focus on studying
When I open my book, I felt asleep just a few mintues later
and I kill my time on browsing website, cliking then icons on the PC
I dont know how to go through this problem, the test is very important to me
someone tell me how to do!

This is called internet addiction. Switch off your computer. If not possible, tell your friend to take it away. you can also visit the mental doctor(I mean psychologist)

Go to your doctor and ask for some pills (more doses than before), take them, go to bed, fold your legs and have a nice sleep.

I also have such feeling
Try to forget the Internet for a period of time
Looking for a classmate that  you can learn together with her or him

Just ask ur friend to lock ur computer, u will feel okay after some times

Just stop your internet service,do not restart it until you finish your test

it's simple. If you always want surf in internet. shut down your computer.

you are have a trouble. you can go to your doctor ,shut down your computer

turn your pc off.
go to school to study.

go to library to study and watch less porn =.=, or cut off your power of your laptop. than evil laugh! MUHAHAHAHA
or tell your parent to sit in ur room