How to split one dialogue (one track) mixed with male and female voices into two tracks

If it's a single track with both voices mixed, then you can't do it. If the voices speak at separate times, then you can edit them into two tracks, but you'll lose all the continuity. The whole point about mixing is that it's like baking a cake - you can't unbake it again.

Even if it's a stereo track with voices split either side of the centre, you won't be able to separate them fully - you will always get a cross-feed of the other voice.