You can create drawing geometry using 2D sketched geometry only, without reference to existing models or assemblies. This sketched geometry can be controlled by relations (collinear, parallel, tangent, and so on), as well as parametric dimensions.
Sketch tools and sketch relations work the same way in a drawing document as they do in a part or assembly document. The only difference is that instead of sketching on model planes or faces, you sketch on the drawing sheet or in an active view.
When you drag a sketch point in a drawing, it snaps or infers to other sketches, drawing views, blocks, and items in the sheet format.
If you add sketch entities to a drawing view, the border automatically resizes to include these items.
Sketch Entity Alignment
You can constrain sketch entities to geometry in multiple drawing views. Use relations as in sketches. In this example, a sketch point in the top view is coincident with the virtual sharp of the part, and the sketched line in the bottom view is coincident with the view's geometry and the sketch point in the top view.
Importing Sketch Geometry
You can import DXF/DWG files into a SOLIDWORKS drawing. Then you can insert that geometry into a sketch to create model features in a part.