Screen does white vertical lines on display

I have been through the same problem ever since I displaced my desktop computer from one room to another. I was used to that in the past but now these vertical lines appearing on my computer screen are becoming too annoying. For a start I used to tap the screen to make the line disappear but recently the problem has become too complex.
The screen image is flickering. I can see that the computer is booting normally and loading windows. I would love to have some help through well structured instructions about how to repair my computer screen. I can manage to do some electronics but thing is that I do not know the exact problem for that issue. I would much appreciate if I am not told to buy another computer screen because I would have to save for another two months to be able to do that.
And for the time being I am at my friend’s place looking for solutions.
