/Library/Spelling not found

I am a new Mac user trying to set up spelling checker for MS Office. I have downloaded the .dic & .aff files that I have to add to my /Library/Spelling folder. However, I have not managed to find this folder. I have looked it up in my Finder and also used Terminals to make files shown, in case it is a hidden one (even though that would not make much sense..), I still havent found the Spelling file.