What do you think about this? Related to the odds of Earth being able to sustain life by chance.?

I recently read (Sorry I can't remember the name of the book) about the odds of Earth being able to sustain life. If it were inches closer or farther from the sun, or the sun was any hotter or colder, it would be inhabitable. Many theists say that god must be real, because these odds are just so miniscule that it could never happen. But, this book explained that we can't think about this subject in terms of regular statistics because the universe is so big. With billions and billions of planets in the universe, the chance only needs to be, say, one in a billion, to occur. And we don't need to search for these few planets because we are already on one, you know? I'm sorry this is really hard to explain and I probably just wrote something completely incoherent. Anyways, do you get what I'm getting at? Haha any thoughts, comments, concerns?