Which CST template should I use for a simple microstrip?

I am a newer for CST, and I am not clear about the CST template.
What i want to know is which template should I choose for a simple microstrip problem. Thanks!

Hi
When you open the template choose the one with GND plane it's written below
the picture of the template. and check the refine mesh.
PL

but what the template mainly about?
bounderay condition?

As the name implies,
template is about the simulation setup. The background material, the boundary conditions,units and such stuff.