The steps for the construction of inscribed circle is:
Bisect one of the angles
Bisect another angle
Where they cross is the center of the inscribed circle, called the incenter
Construct a perpendicular from the center point to one side of the triangle
Place compass on the center point, adjust its length to where the perpendicular crosses the triangle, and draw your inscribed circle.
Clearly from the figure we could see that Sumi is trying to construct the angle bisector of ∠D as she has drawn the arcs GH by placing the point of compass at point D.
So now she need to join the Point D to Point P to get the angle bisector of ∠D.