A family of Microsoft word processing software products for creating web, email, and print documents.
You have somehow formatted your Normal.dotm template as two columns. That isn't easy to do!
To fix it, close Word. In Windows File Explorer, click the View tab and check the box for "Hidden items". Then find the Normal.dotm file (it should be in the folder C:\Users<your login name>\AppData\Roaming\Microsoft\Templates), and rename the file to OldNormal.dotm. When you restart Word, the program will automatically create a new Normal.dotm template, and you should be back to one column.
If the old Normal.dotm template had important customizations such as custom styles, you can transfer most of them to the new template by using the Organizer (http://www.addbalance.com/usersguide/styles.htm#Organizer ).