How to block content from Google?

I have never seen a situation where you need to block content from google. Google doesnt support a method for us to block content. They explain in the video below.  I agree with them because I have never needed to block content. (apart from block pages with sensitive details on)

You can put your content in an iframe and have it blocked by robots txt. Please check out the video below.

Can I exclude certain words from Googlebot?