If you place model text into a family, it acts like a nested family, and the format can be controlled by parameters in the host family.
You can create parameters in the host family to control the text, text size, and depth, and to toggle between bold and italic for the model text in the project.
To control text
Model panel
(Model Text), and then type the text in the Edit Text dialog.
Properties panel
(Family Types), and add a family parameter that is of type text. This will be the parameter that controls the text of the model text in the project.
The model text updates to the new value. If you created an instance parameter, just the one instance changes. If you created a type parameter, all current and future instances of the model text change.
To control depth
Controlling model text depth is similar to controlling text, except that you create a family parameter that is of type length. Follow the above procedure to associate parameters for model text depth.