Before you start drawing the window, assemble a collection of edited dwgs or jpgs that can be inserted into the elevation and plan views.

Create a new metric window family, delete the existing opening cut.

Highlight the wall and edit the structure, extend the width, length and height to accomodate a large window.

Create a void blend to establish the main cutout and then use extrusions to form the window frame, glazing bars and glass.

Sweeps can be used to add more detail.

Arrays could be used to locate the horizontal and vertical glazing bars.