three expression above are almost same meaning and purpose. but it has quite small different feeling to listener (nuiance) 1) 할 거예요 = future tense, not right now but soon. 2) 할게요 = let me do it (favorable ways to say someone) 3) 할래요 = including hope, wants (but not very strong hope) I cannot know how to explain its difference in English. As far as i know, English or other European language have no expression or utterance exactly in accordance with that of korean

Which one (do ~ 할게요)you ? How long will you (do? ~할 거에요?) Ah~ Example sentence A: Do what I do ! B: Yes i (do , 할게요)it (In korea polite ``do`` speaking word is 할꺼에요) Mr Kim Min Sung is right