Hey Jdudeo,
please excuse me if this part was confusing in the manual – the blog posts page in WordPress is set via the “Settings -> Reading” admin menu, the second half of the “Front page displays” option; the “404” page is a separate template which is used automatically for any URL that does not exist on the website, i.e. an error page. You can type anything after your website’s home URL and visit that address to see the “404” page ;)
I will rewrite and expand this place in the theme manual, thank you for pointing this out!
Sincerely,
Andrew / Satori Studio