How do you tell the difference between the male and female plant.
Generally, when you look at the flowers, there will be a big difference in the organs. For the male, you will notice many pollen bearing stamen. For the female, there will be no pollen powder and it will have one central stigma. This is what receives pollen.
Here is an article for more information on the care of the plant:
https://www.gardeningknowhow.com/ornamental/shrubs/mountain-pepper/growing-mountain-pepper-plant.htm