Word's alignment guides can help you align objects such as images, text boxes, etc. with the margins, vertical center, and horizontal center on the page. From the Layout tab, select:
Align | Use Alignment Guides
The following image shows the green alignment guides positioning a text box in the lower-left corner of a page. The vertical line is the left margin and the horizontal line is the bottom margin.
To align objects with each other, select the objects and from the Layout tab, select:
Then select the way you want to align the objects.