You can find any tool by the Menu Structure HERE: https://turbocaddoc.atlassian.net/wiki/display/TC21UG/Menu+Structure

You can find the menu location of any tool by name HERE: https://turbocaddoc.atlassian.net/wiki/display/TC21UG/Tools+Mapped+to+Menus

Select by Layer

Hotkey: Ctrl+L
  
Selects objects that lie on specific layers (see Snap Modes).

Press Shift to select a range of layers from the list. Press Ctrl select or deselect individual layers.

Add to current selection: All objects selected by the layer match will be added to any current selection in the drawing.