Note Some AutoShapes such as lines, connectors, and some freeform drawings, have no room for text. While you can't add text to the shape, you can place it near the shape. Just add a text box, place it close to the shape, and then type your text in the text box.
Note The text box will not move when you move the shape unless you group the text box and shape.
You can select one object in a grouped object without ungrouping it. Hold down the SHIFT key while clicking on the object you want to select.