In English, if someone asks you to do something a common way to reply is “Yeah, I will.”
Which is of course a shorthand for “I will do that.”
“Please remind me every day, to take a shower.”
“Oh, I will. Believe me. I will.”
The most literal translation of that in German would be “Ja, werd’ ich.” but that’s not what people actually say.
Instead, what people say is:
“Ja, mach ich.”
German essentially uses present tense here, and even if that might feel weird to you, it’s completely consistent because German generally doesn’t use its future tense very much, especially in spoken German.
So, suppose you’re going to get another beer at the bar and your date asks you to bring them one as well, what you could say is:
“Nein, geh selber. Wir sind noch nicht verheiratet.”
“No, go yourself. We aren’t married yet.”
That’s… uh… very risky, though.
The normal reply is of course:
“Ja, mach ich.”