Refer to tutorials on how to create pattern based curtain panels.
WHERE ARE ALL THE CURTAIN PANEL PATTERNS?
Your project may not have any Curtain Panel By Pattern families loaded.
You will find them in the Revit libraries.
Revit standard in: . . . \Revit Libraries\External Libraries\2011 AutoDesk\International Library\Curtain Panel By Pattern
Approved in: . . . \Revit Libraries\Approved Library\Curtain Panel By Pattern
Load them from the ribbon using Insert > Load Family.
HOW TO CREATE MULLIONS
You can't apply mullions to pattern based masses like ordinary curtain panels. They must be modelled as part of the pattern based curtain panel.
Place a Point mid point of each edge reference line.
Draw a profile using model lines of the mullion at each of these points, centred on the reference line. (hint - do a circle, snap to it to draw other shapes, then delete circle).
Select one reference line and its profile, select Create Form.
Repeat for each reference line.
This method leaves a gap at intersections, which ensures cleaner looking intersections on the curtain wall.
Unfortunately mullions at edges will have a gap.
Use an adaptive component family to fix these anomalies, including edges of patterns where curtain panels don't finish in full. (RH)