"I look back at when I was a kid, and I notice how blind I was. It seems like I was inside a shell that blocked the view of Earth.

What does that mean?"

It means you were sheltered. It's pretty much the same for every kid at a young age. As you grow up, you become more exposed to the outside world until you reach the point where you just want to crawl back up your mothers snatch and sleep your life away.