my friend copied some files from his computer and he wrote on the cd and it has gone through the upper surface so when u look at the cd upside down u can see what has been wrote. and i cant get the files to load up. is it lost forever or is there a way to get it back
If it's the non label the reading side that's damaged you can often buff the surface up using Cd scratch remover. If it's the top/label side that's damaged maybe with a ball point pen as hector 911 says the data is probably destroyed.
As a last resort you could try some silver or white nail polish painted over the writing on the label side of the disk. Try just a thin layer at first and add some more if necessary. Make sure the nail polish is dry before trying to use the CD.