What is wrong with my laptop?

A while ago I was wiping my Macbook Air with a soggy dishcloth. There may have been too much water because right after that my screen turned rainbow colored and it could not work. Now a few months later, I turned on the same laptop and it is displaying a white screen. I was thinking I can replace the screen easily but if it is something wrong with the moniters or the inner functions of the laptop then it will be a lot more complicated. I’m not a tech genius or anything so can someone walk me through what is wrong?