You draw when you are placing lines and points to create a form. You can draw on the following elements:
3D levels and 3D reference planes are automatically detected. They highlight in the drawing area as the cursor moves over them. Click to select one of these to set it as the active work plane.
Draw panel
Line.
Draw panel
Reference before selecting a drawing tool. See Unconstrained and Referenced-Based Forms. Several options become available on the Options Bar. You can set the placement plane, create a surface by drawing closed profiles, draw a chain of lines, and set an offset or radius value.
Draw panel
Draw on Face to draw on a surface, or click Modify | Lines
Draw panel
Draw on Work Plane to draw on a work plane.
Select panel
Modify.