Having trouble creating basic VGUI

Following the tutorial found here to get a handle on the basics of Lua. My problem right now, and my brother can’t find it either (He says it should work) is that anytime I run the conCommand in the example, I get thrown a lua error.

testLua.lua:22: attempt to index global ‘vgui’ (a nil value)

I’ve taken a perfect copy of the example one, which returns the exact same problem. Any ideas/suggestions as to what I’m doing wrong?

Edit:

Fixed the directory structure: Must have been trying to run it as a server. Problem is fixed.