responded in the wrong thread, sorry.
>>839549 (OP)
I'm Romanian so there's no reason for me to study another Orthodox language.
Despite my personal taste, I think Greek will be very useful if you'd like to learn it. The "original" books of the Bible are in Greek and there are a ton more Orthodox books in Greek as well.
As for language learning, you will have to read a lot in said language. It's the only way you can acquire a language.
Personally I like Russian way more than greek and you can actually speak it and perhaps find more materials (including secular) for immersion than in Greek.
I'm not sure what the situation is where you are, or if you're even the US. But, can't you easily find Churches with service in English?