How to dissociate connected lines:

Hello,
I know this may sound confusing but would anyone know how to disconnect a line from another set of lines so when I select the line it does not select other connected lines? If you look in the picture below, I am attempting to select only the border of the drawing and not the interior, but every time I select the border it selects the connected lines on the inside as well. I am trying to use this file for laser cutting and it is obviously a major problem when it come to determining what lines will be etched and what lines will be cut. Thank you if this makes any sense.

Are you sure the lines are not inside a group?

They are not inside a group, nor can I explode the entire drawing

Example 2 If you were to select all connected of one side it would select the interior as well as the outline. I would just like to obtain an outline, and making a component or group does not help as it would not apply inside of the laser cutter software.

Thank you