If you are using Microsoft Word 2007 or later, here is the way to make Portrait or Landscape as the default view of a Document. Do note that any documents created earlier will remain in the way as they were created and this change now will be in effect for all new documents created hence. Also remember that while printing this document, MS word remembers the format and prints it in the same way. For example, if Word is setup to show in Landscape mode by default, the documents will be printed in Landscape mode only.
Open any Word document and click on the Page Layout tab in the top horizontal menu. While you are there, you can find ‘Page Setup’ as the second block of configurable options. Now open the Page Setup dialog box (you can find a small Pop out like Symbol at the bottom right corner of the Page Setup block). There you can find Portrait and Landscape options under Orientation. Select any one as you like and click on ‘Default…’ present at the bottom. If a Dialog box opens asking if you want to confirm the changes, select Yes.
The same process should be used to switch back to the previous view mode.