Do you know what kinds you have? If not do you have photos?

Some are easy to propagate by cuttings--in fact many of the commonly available kinds are.

Often passionflowers are self-infertile, so you won't get fruit/seed without a plant of a different clone around. Sometimes a different species will work. And sometimes you don't have the right insects (or birds or bats, I suppose) around and so you would have to hand pollinate. And some hybrids are sterile--you will never get fruit.

There are techqniques besides cuttings and seeds, but those are the most straightforward and for most plants they suffice.