What do you mean, you're the one I'm willing to do nothing for?

You are the person I am willing to give everything for, which means that I only care about you, your money, other external things, and the influence you have brought me.

When a girl says such a thing, it shows that she cares about this boy very much, and when a boy says such a thing, it also shows that the feelings between two people are deep. They are each other's partners, people who will accompany them for life.