Hi Sonia. The first one is correct! Definition I sure will!: Certainly I will! Of course I will! Example "Trey : I sure will Miss DeLune." The second one is more comon in this way. Definition I will SURELY do!: I will certainly do! Of course I will do that! Example "Jane: Yes, I will surely do that." "My classmates will surely do better" "They will surely do so again" I hope that can help you!

'I sure will' sounds good, but I think 'sure' needs to proceed 'will' because 'I will sure do' is strange. So you could also say, 'I sure will do', but the exact meaning of 'do' has to made clear from the context. For example A: You take care of yourself! B: I sure will do! ( do - take care of myself) Otherwise, 'do' needs an object: I sure will do it