Greek is not an easy language, and is especially difficult to read if you haven't studied it at school or college, as the
alphabet is a lot different to ours.
Despite the fact that the majority of the Greeks - particularly the young people speak a little English, it is useful to have a basic knowledge of the language.
In particular because the names of the places are not always written in the English language.
In addition it is always nice to say a few words in Greek, like e.g. good day, good morning or to be able to say thanks for the hospitality you have received.
In every bookstore you can find a book that is dedicated to the Greek language.