In Greece and Cyprus, the official language is Modern Greek We learned Ancient Greek at school but if you are not studying at the university, that's why all Greeks do not know Greek at a proficient level, it is very hard to know it properly. It is different and harder than Modern Greek. In my opinion, if you want to learn Ancient Greek you need a teacher. Modern Greek is a language based on Ancient Greek. That means if you already learned Ancient Greek it will be easier for you to learn Modern Greek. If I can make a comparison between Polish and Greek, I can tell you that Greek is much easy than Polish, because if you know the alphabet you can read everything, I hope you find my explanations helpful and start learning this beautiful language. https://www.britannica.com/topic/Greek-language/The-middle-phases-Koine-and-Byzantine-Greek

Thank you so much Venetia for your explanations. :-)

Hello! There are all Greek but from a different age. Ι studied Classics (Ancient Greek, Latins) and I had some lessons in Byzantine studies. In my opinion, firstly you have to learn Modern Greek because they are much easier. After a basic level, you can proceed to the other. The Byzantine do not have a big difference with modern Greek language.

Anybody here? :-)