Well you don’t have to have both to be intersex, but that is the most commonly known form. An intersex person does not have sexual organs that are exclusively male or female. There are many, MANY of ways for someone to be intersex, and it is a spectrum rather than an absolute. Some just have make or female bodies, and, in puberty, get horomones that are used for development of the other biological sex. Most have more than two chromosomes in their cells. A large amount of intersex people, however, can reproduce perfectly fine, and not have a very high chance of passing on the traits that cause it.