BREAKLINE is from Express Tools, which is not available in AutoCAD for Mac.
You can search the Internet for AutoLISP routines, that creates breakline symbols.
I have one, that I use on daily basics. You can try it - after you APPLOAD it to the drawing, use BRKL command to draw breakline. I attached two versions - one for metric units (1 AutoCAD unit = 1 mm - BREAKLINE.LSP), and other for imperial (1 AutoCAD unit = 1 inch -BREAKLINE-I.LSP). Both routines uses DIMSCALE variable to set scale factor of the breakline symbol.