How to say: why is it written in Korean?

How to say "I can't call you right now" in Korean

How to say lamp in korean? Not "램프" (like the genie in the lamp, lamp) Lamp as in the source of light!? :-) Answers are highly appreciated​

What does "거기서 뭐해요?" Mean?

This is kinda a hard question but how do you say Cortical Dysplasia in Korean? I wasn't sure if I should just ask my doctor for help on this or not but a while ago I was diagnosed with Cortical Dysplasia (a very tiny part of my brain that causes me to have the possibility of a seizure (Intractable epilepsy)) I'm not asking how to say epilepsy, but I'm asking how to say the birth defect Cortical Dysplasia.

How to say "Hello my name is ___ but, you can call me ___." In Korean? I know how to say "Hello my name is ____" (안녕하세요 (제 이름은) ____ 입니다) but my name is really hard to pronounce in Korean, (my name is Faith (페이스)). Kinda sounds like face or pace lol. so I would like to tell my soon to be host family my nickname! But I wasn't sure how to say "But you can call me ___."

What does "한국은 와밨어요?" mean? My Korean friend texted me this and I'm not sure what is means?

How do you say "Have you heard ___'s song?" in korean? And "do you like ___'s song?"

What does this mean? 다이어트는너무힘든거같아... Something about a diet? My Korean friend texted me this and I'm not quite sure what she means!