Convert jpeg to dimensional cad drawing

Attached are many JPEG images of an existing wood walkway. I need the walkway roughly converted into a detailed CAD drawing. No dimension are required at this phase. The drawing should accurately represent the framing layout and include all structural members, dimensions, and spacing. I will provide the lumber sizes, including length, width, and thickness for all materials used in the frame after the first phase. The first phase will deliver a drawing that I can then print out and write all dimensions on and submit for phase two. In Phase two the drawing will be properly scaled with all materials and measurements indicated. This is to be used for construction purposes. Experience in cad work for structure design is required