Well I am not sure what you exactly mean, but usually people say: yes I will. Yes I do. Yes I did. Yes I am.

You can not say those two phrases as affirmatives. You can say one of the following: "It will do", "That will do", "It'll do", "That'll do", "yes, that's good", "yes, that works". Other ways to also say "yes" could be: "correct, right, perfect, great, yup, yeah" depending on context and formality. I hope that helps.