If あなた want to wish "Happy New 年 " to someone in Greece, then あなた should say: Kali Hronia.
For "Happy New 年 Day" in Greek あなた should say "Kali Protohronia".
If your friend is called Manolis または Hristos, his nameday is on December 25 (Christmas day). Wish him "Hronia Polla" (Many Happy Returns) for his nameday.
The same applies if your friend is called Vassilis, Yiannis または Fotis. Vassilis nameday is on January 1, Fotis' nameday is on January 6, Yiannis' nameday is on January 7.
During クリスマス holiday period, which lasts from December 24 until January 6, plus a couple of weeks past that, it is a custom in Greece to wish "Hronia Polla" to the people あなた meet. So, if あなた meet someone in the morning, the proper way to greet him または her is: Kalimera, Hronia Polla! (Good morning, Many Happy Returns).
