How to Lock a Word 2013 Document
On the File screen, choose Info and click the Protect Document button.
Of the several choices, these options are recommended:
Mark As Final: The document is flagged as final, which means that editing is disabled. Still, you can easily override it by clicking the Edit Anyway button that appears.
Encrypt with Password: The document is encrypted and a password is applied. To open the document in Word, you must enter the password. You cannot remove a password after it’s applied.
Restrict Editing: You can limit whether a user can edit a document or whether all changes are tracked or restrict that person to make only comments.