Technically you dont need a file just delete it/ leave it deleted and you can still open a blank document.

If your OCD makes you recreate it then just follow these steps:

So you've changed/deleted/got an old version of your blank word document template

go to 

%appdata%\\Microsoft\\Templates\\

and rename normal.dotm to something else like add an undefscore to the end or .old

sart a new document in word, styles little corner box, drop down on the right of a style, change something like the font size , select 'new documents based on this documents' then OK. New file should be created. Go back and revert the change you made back again and you are off.

https://answers.microsoft.com/en-us/msoffice/forum/msoffice_word-mso_other/how-can-i-restore-normaldotm-to-a-virgin-state/99d1f145-8b55-e011-8dfc-68b599b31bf5

Dont forget your personal letterhead post here