Well, I'm not confused by that question, so maybe I should be Prime Minister...
Woman: A member of the species Homo Sapiens Sapiens who, in the normal course of events, will at some point in their life be capable of biologically conceiving, carrying a foetus and bearing offspring.
Man: A member of the species Homo Sapiens Sapiens who, in the normal course of events, will at some point during their life be capable biologically producing sperm and biologically fathering offspring.
If a man wants to change his gender to female, they cannot be designated as a woman unless they are able to conceive, carry a foetus and bear offspring.
If a woman wants to change her gender to male, they cannot be designated as a man unless they are able to biologically produce sperm and biologically father offspring