Go to Design > Page Borders. Make selections for how you want the border to look. To adjust the distance between the border and the edge of the page, select Options. Make your changes and select OK. Select OK.

To add a page border, put the cursor at the beginning of your document or at the beginning of an existing section in your document. Then, click the "Design" tab. In the "Page Background" section of the "Design" tab, click "Page Borders". The "Borders and Shading" dialog box displays.

To use Word’s built-in page borders, follow the steps below. Open your Word document and select the Design tab on the ribbon bar. Press the Page Borders option in the Page Background section. In the Borders and Shading dialog box, select the Page Border tab. In the Setting section group on the left, choose the type of border you want.