If, when someone asks you "why do you believe as you do," you can't explain your reasoning, but instead cite a source of information, then your beliefs are not your own, and that is what makes you a sheep. It doesn't matter what you believe, it matters why you believe it.

Is there life out there? Most certainly, because the right chemical environment will, through a process called abiogenesis, give rise to living organisms. Given enough time, advanced multicellular life will eventually emerge. On Earth, that process took about 3 billion years.

Have we been visited by aliens? Well, probably, but not in the way you might expect. In 1969, a 4,5 billion-year-old meteor impacted Australia, and when it was examined, it was discovered to contain 80 amino acids and other organic chemicals of extreme complexity, lending credence to the "panspermia" hypothesis, or that the Earth was "seeded" with life from outer space. We might be descended from extraterrestrials, though it's unlikely.