"저는 여자에게 선물을 줍니다."
Translation:I give the woman a present.
Korean does not have specific particles or words for indefinite articles "a" or "an". If you want to say you are talking about a specific person etc, you can use "그" (that) as a standalone modifier word right before a noun to represent the English "the".
Otherwise the conversation without that will sometimes give you clues to know if the most natural translation into English works best with ”the or "a/an".
I'm always considering: Literal translations do not always work from one language into another.
I'm always considering that "what" is not always "왜" , "to" is not always "에게".