...
Next, we need to create a surface from the sketch. In the menu tool bar, select Concept > Surface from Edges. In the graphics window, the perimeter of the sketch by either holding CTRL and selecting each line, or holding down the left mouse button and dragging the cursor over each line.
Next, in the details window, select Geometry Edges > Apply. Finally, press . The final geometry should now look like the figure below.
...