Unable to add material to brazier tutorial

I am completely new to this engine, so I decided to go ahead with the tutorial program. The first stop was to create the brazier.
During this, I was having issues with the tutorial particle system not showing the material, so I attempted to add the proper texture.
However, I am unable to add ANY texture to the Material section, so all I see are those ugly squares coming from it.
How can I fix this issue with the material section?

Also, the tutorial particle system icon has a small red triangle in the top right of it in the content browser. Could this also be connected to this particular issue?

Any and all help would be greatly appreciated.