Parametric Cell Studio, starting up question, how to use Substitute Component command??

Dear All

In a Parametric Cell Studio demo video<Bld_US_prd_Parametric_Design_Part_03_Hangar_with_Steel_Framework>, the author by clicking on the SUbstitute Component command. Pulls out a selection dialog box, choose the way to change the section of the selected objects.

 

but how to set?What is the implementation of this Substitute Component command?