How can I attach a Microsoft Word form to our form?

I need to be able to add a word document that clients can fill out and submit with their form. It has to stay in the word document layout because it is an official form that can't be altered. 

You would need to add a downloadable link to the file in the form.  Here is more information on how to do so:

https://www.jotform.com/help/431-How-to-Add-a-Downloadable-File-to-Your-Form

Then simply add a file upload field to allow for uploading the document once they have downloaded it and filled it out.

https://www.jotform.com/help/332-How-to-Create-File-Upload-Forms