How do I select multiple items in Word so that I can move them at the same time?

DBP-User the easiest way to select a variety of 'objects' on a page is to open the Selection Plane on the Home Tab

Once you have the Selection Pane open, then hold down your Ctrl key to select individual items you wish to work with.  

You can also 'Group' them together as 'one object' in the Arrange Commands that way it's easier to move them around as one:

If you want to know more about the Selection Pane, this may help : Manage objects with the Selection Pane (microsoft.com)

If you want to know more about Grouping, this may help: Group shapes, pictures, or other objects in Word (microsoft.com)