To do certain things with an object (change the font, move it, resize it, etc.), you first have to select it. Select means to point to the object with the mouse and then to click the left mouse button.
To select a single object
Click on the object.
Sizing handles appear around the object to indicate that it is selected.
Selecting multiple objects
Hold down the Shift key and click on the objects you want to select.
Handles appear on each selected object. You can then move or delete the objects as a group. You can also change the font or text formatting for all selected objects in one operation.