The Rectangle button allows to draw a closed rectangular polyline.
Quick Access Panel: 
Ribbon: Editor -> Draw -> Rectangle
Menu: Draw -> Rectangle
The rectangle has all the properties of a polyline.
To add a rectangular
1. Click on the icon .
2. Click to start drawing the first corner or enter the coordinates via the dynamic input.
3. Drag the pointer diagonally in the direction you want, to draw a square-cornered shape.
4. Press Enter or left click.
Go to CADEditorX
URL of this topic:
https://cadsofttools.de/help/cadeditorx/index.html?draw_menu_rectangle.htm