The above is incorrect. The “sudo” part is correct, but the file is not an editor. You need an editor to open that file rather than treating the file itself as an editor. Do you have a favorite editor? As an example I will use “nano”, which is a very simple text editor with a list of its commands at the bottom (the “^” in front of letters in the menu list is the “control”/“CNTL” character): sudo nano /etc/X11/xorg.conf
(and for example CTRL-x exits)
Another option might be something like gedit (or kwrite if you have it installed).