What do Wiccan's believe created the universe?

I'm mostly agnostic, but I want to study religion, and Wicca really interests me. I understand the Horned God and the Triple Goddess are the main central deities. I just want to know the Wiccan belief of how the world came to be. Which deity played a part in creation, and how do other deities of other religions (such as ancient Egyptian ones) play a part in your belief? Do you worship only one, or all? Thanks for genuine answers!