Ex: Convert 2D Object

Draw a 2D object by polyline

Select the 2D object

Properties palette
Thickness: 10

Home tab > Solid Editing panel expand > Convert to Surface

Select the polyline with thickness

Press Enter

Status bar - Selection Cycling

Select the polyline
Select Surface (Extrusion) on the Selection dialog box

Home tab > Solid Editing panel > Thicken

Input 1 for the thickness

Thicken only work on surface