Hi s7r83dg3,

> ... I mean the selected surface -> edge

Do you mean you want to extract the edges of a surface as regular curve objects that are independent from the surface?

You can do that by using Copy + Paste when the edges are selected.

You can also use "Select All" as a quick way to get all the edges of a surface selected - first select one edge by the regular method of a second click on it. That's where the first click selects the "whole object" and then the second click can drill-down to select sub-objects like edges or faces.

Then once one edge is selected use Ctrl+A (or the "Sel all" button on the Select tools section of the side pane) - that will select all other edges and now you are ready to do a Ctrl+C Copy and then a Ctrl+V paste to duplicate them as individual separate objects.

Then delete the surface if you don't want it anymore and just want the edge curves.

- Michael