I can't get a spotlight to work properly in Unity.

The way I have been trying it the halo of the spotlight is viable and is acting according to what I need it to do, but the spotlight itself isn’t showing any light within the cone I have created.

A screenshot often helps when asking about graphics issues, but what you’re describing sounds totally normal - you can’t see the beam of a spotlight as it travels through the air; you only see the lit surface on the object which it illuminates.
Were you looking for volumetric lighting instead?