Macro Scheduler 12 ships with a comprehensive help system (.chm). You can hit F1 at any point in the software, click Help on a code builder or press F1 while the cursor is positioned over a command to get context sensitive command help, or choose one of the options in the Help menu.
But if you prefer a different format there are some other options:
Online Help: You can view the documentation online here.
PDF Manual: You can download a 218 page PDF manual for free.
Perfect-bound Dead-tree Manual: You can purchase the 218 page manual in smart physical book form for $19/£19/€19 including world-wide shipping from here.