Translation:I am a person.
that's the variation of formal speech. like towards older or senior folks you use 조는 but the formal casual form (in which you use towards other people in general) is 제가 and this quite shows how inconsistent duolingo is. if you really want to learn korean you can't depend on this one only
저 means that, 가 is a subject marker used after a vowel. 져가 means (져 means my) I when you are the subject in the sentance. 는 is a topic marker. So 저는 is I also but in the sentance you are the main topic of it or you are talking about yourself. 나는 is a least formal way to say it. 네가 means you. (I THINK BECAUSE I AM ALSO JUST LEARNING, IF I AM WRONG PLEASE DON'T DOWNVOTE IT, TELL ME WHY IS IT WRONG, THANKS!!!)
So everyone is so confused at the ending word 'ip mi da' but because I speak urdu I found it not confusing,I just found out korean and urdu have the same grammer omg I am soo happy. :) Yay! I think just, I think that 'ip mi da' is a sentence ending thing btw The sentence I am a person (lol) doulingo is confused if I am a human,robot or animal.Lmao