"you are welcome" 은 "당신은 환영입니다." 이지만, 이렇게 쓰지는 않고요... 보통 사람들은 "천만에요 ^^" 또는 "뭐 별것도 아닌데요" or "뭘 그런걸 가지고" 등등 사용한답니다. "you're welcome" is "당신은 환영입니다." but didn't use it... people usually said "천만에요", "뭐 별것도 아닌데요(that's is nothing)" or "뭘 이런걸 가지고(this is too small thing you appreciate)"

천만에요 is not really used. Check out this video for more detail: https://youtu.be/2RRKNE3Fjzo

When someone says "Thank you", we just smile in everyday life. We say "뭘요"(most common) or " 별 거 아니에요" when we want to say something.