Are you freaking serious? I mean come on, are you FIVE or something? You've asked if one myth is true, and how to become two different mythological creatures. Seriously, these things don't exist. Just freaking grow up already, I'm sick of this.
The answer to your question is, you don't. Vampires don't exist. There are pale people who pretend to be vampires and claim they drink blood and stuff, but when you get right down to it, they're just a bunch of, well, like I said, pale people who pretend to be vampires and claim to drink blood.