Perhaps some more basic info first: a path is in fact a series of point interconnected by lines whose curvature is described in mathematical formulae. Which means, in everyday speak, that they cannot be seen. What you do see is Photoshop acting as if, and showing you a replacement line.
What you have to do to make them visible, is to stroke them. And it's in the stroke that you choose your 2pixels.
The line's curvature and length is the path.
To get a first try, you can use the freeform pentool. Just draw a line with it. Then, when you're finished, alt-click on the black arrow tool on the toolbox to select the white arrow tool, or direct selection tool. With this tool, you can change the shape of the line by dragging points or segment. And much more. Just change the shape a bit, and then stroke the path.
This you do by alt-clicking on the second icon from the left at the bottom of the paths palette, the stroke path icon. This shows you the stroke dialog box. Here you get an idea of what you can do with your path. And that is much more than only draw as many, many tools are in the dropdown list...
have fun!
