Please, correct me!
I wrote a messange but it sounds awkward even for me xD Because I don't know how to say it in a natural way. Could you please correct what wrote to be sounded more natural?

"몇 살 먹었다 라는 칠문은 친구들과만 사용할 수 있어? 좀전에 잘 모르는 만난 사람과 이 말 사용해도 돼?"

(The expression "몇 살 먹었다" can be used only among friends? Can I use it with people that I met no so long ago and who I don't know well?)

Question

Please, correct me!
I wrote a messange but it sounds awkward even for me xD Because I don't know how to say it in a natural way. Could you please correct what wrote to be sounded more natural?

"몇 살 먹었다 라는 칠문은 친구들과만 사용할 수 있어? 좀전에 잘 모르는 만난 사람과 이 말 사용해도 돼?"

(The expression "몇 살 먹었다" can be used only among friends? Can I use it with people that I met no so long ago and who I don't know well?)

Answer

Short Answer: NOPE

"'몇 살 먹었다' 라는 질문은 친구들 사이에만 사용할 수 있어? 좀전에 만난 잘 모르는 사람과 이 말 사용해도 돼?"
When you saying like this in Korea, in public place like here, it's rude.

"'몇 살 먹었다' 라는 질문은 친구들 사이에만 사용할 수 있나요? 좀전에 만난 잘 모르는 사람과 이 말을 써도 되나요?"

Please, ask politely when you asking someone in the Internet or real life.

You must use a polite form with unknown people.
Alternative. "나이가 어떻게 되시죠?. "