Color The Page In Word. Under Printing Options select Print background colors and images. Click on one of the rectangles and in the Format tab in the ribbon click the Shape Fill then select a color.
To add a gradient. Click Fill Effects to add special effects such as gradients textures or patterns. If you dont see the color you want select More.
Go to File Options.
Click the Insert tab click Shapes in the Illustrations group click the Rectangle shape and size it to the paper. Please see below for steps. It means that you change the default white to any other colour or with a fill effect even. Go the page of the document that you want to change its page color and then click Insert Shapes Rectangle see.