I've met a few men who I swore were gay, but were married to women. Also, not to sound weird, but I've met a few effeminate white guys who were married to asian women, its a strange correlation.
So it seems to be fairly common that effeminate gay men have managed to marry women and have children, but perhaps are still in the closet, or transitioned out of the closet. So I wouldn't say its completely impossible for a gay man to decide he wants to have biological children and become a father.
You do know that being gay involves being sexually attracted to similar genitalia and not whether a man is interested in football or Broadway?