How to introduce myself and difference between 이름 and 성함
I first learned to introduce myself simply like "안녕하세요 Rhea-ㅐ요 " Is this polite? When is this appropriate if at all?요

I then learned " 제 이름은 Rhea 입니다 " Is this correct? (I think I've decided on 래이야 for the Korean spelling of my name ^_^)

" 성한 " is another word for name, but I read that it is only used in specific occasions, can someone clarify this?

Thanks! :D

Question

How to introduce myself and difference between  이름 and 성함
I first learned to introduce myself simply like "안녕하세요  Rhea-ㅐ요 " Is this polite? When is this appropriate if at all?요
 
I then learned "  제 이름은 Rhea 입니다 " Is this correct? (I think I've decided on  래이야 for the Korean spelling of my name ^_^)

" 성한 " is another word for name, but I read that it is only used in specific occasions, can someone clarify this?

Thanks! :D

Answer

저는 Rhea예요 would be OK for a friendly, not too formal situation.

'입니다 ' is the ending you use when talking to superiors or in a more formal situation. So you could say 저는 Rhea 입니다 or 제 이름은 Rhea 입니다.

성함 (not 성한) is the honorific word for name. So if you were talking to or about a 'superior' person, or being polite, you could say 성함이 어떻게 되세요 to ask their name.