If you open a multiline text object's Properties (see Object Properties), there are certain parameters of the text you can edit. To edit the text itself, and for all properties not available on this window.
The properties also appear in the Selection Info palette, when the multiline text is selected. All parameters can be edited, except for the text string itself.
Font: Sets the font name, style, and height.
Mode: Select Scalable for text that can be re-sized non-proportionally or Flexible if you want pen, brush and slant options available.
Oblique Angle: Available for Flexible mode only, sets the slant of the text (slant of each character).
Width Factor: Sets the width of each character.
Justification: Adjusts the text relative to its paragraph box.
Factor: Sets the distance between lines.
Style: Select At Least to automatically set the line size relative to the largest character of a line. Select Exactly to keep all lines the same size.
Angle: Sets the angle of the paragraph.
Width: Sets the width of the paragraph.