how to answer in korean
when someone asked 잘지내?
i know it means (how are u?)
but is it correct to say ( 전 괜찮아 ??)
to say (im okay) or (im fine )

Question

how to answer in korean
when someone asked  잘지내?
i know it means (how are u?)
but is it correct to say ( 전 괜찮아 ??)
to say (im okay) or (im fine )

Answer

We usually reply like....
"응or 어, 잘 지내.(=yeah, I am fine or ok) 넌?" among close friends for "잘 지내?"
We wouldn't say "전 괜찮아" for "I am fine" because "전" is a polite form and "괜찮아" is not polite.
It should be "전 괜찮아요" with "요".

Here are possible responses for that.
(not polite, among close friends)
A: 잘 지내?
B: 응. 잘 지내. 넌? (I'm fine or ok)

(polite, informal)
A: 잘 시내시죠?
B: 예. 잘 지내고 있어요.(=I am fine or ok)

(polite, formal)
A: 잘 지내십니까?
B: 예, 잘 지내고 있습니다.(=I am fine or ok)

\^o^/

Answer

Usually, it's 잘 지냈어요. 
But some say 그저 그래요. (So-so)

Answer

Check this video; https://youtu.be/aG0TMm8aWkQ