Assuming that your drawing page is already set to the proper scaling, the
easiest way to check the size of the shapes as you place them is via the Size
and Position window (menu bar > View > Size and Position Window). This
provides a info on the selected shape, and you can enter desired size
information.
There are dimensioning stencils available, both architectural and
engineering, DIMARC_(U,M).VSS, DIMENG_(U,M).VSS, and drawing tool shapes,
DRAWTL_(U,M).VSS; where either the U or M designates US or Metric units.
These shapes may be positioning anywhere on the drawing to measure distances
between shapes or sizes of shapes.
HTH
Wapperdude