Asa Butterfield on talking to students

The video begins with a humorous introduction, then explores different reasons for certain actions. It discusses the role of lights in film and transitions from space themes to a focus on Blighty, providing a diverse range of topics in a short span.

What does the speaker mean by 'It's funny 'cause I'm sure'?

In what way does the text suggest that 'a lot of film starts in space states'?