If you speak arabic, spell "J" like خ

Your question is confusing, but assuming that you´re learning spanish the sound of "J" always sound like the "H" of english (ex: Here, Hope, etc.) Joven, Joyas, Jamaica. Sounds like John, Jim, are not proper of spanish. So if you see a "J" in a text in spanish it´s always like "here" sound, but if you see an english name just pronounce it like you always do.