Fundamentals of Attaching XSD and using XML in Word Document

Hi,
I have some very basic questions about creating an XSD (or several) to
use in structured documenting with Microsoft Office programs
(Initially Word), but frankly the Microsoft approach to introducing
and developing knowledge in this topic is the opposite of there.

I have tried to attach the seemingly default action pack - not found.
When I create a valid XSD, it won't attach.

Its simple - I just want sections of my documents to be held in
simple, portable, xml to feed ongoing documents further down a project
cycle.

I wonder, if I succeed and I try to save the content from the xsd I
have created, will my content get lost in a lot of junk that Microsoft
throw in for formatting (and obfuscation?)

Is there a good start point for creating documents, sheets, whatever,
so that the reasonable goal of having a formal document with content
managed via xml (e.g. to facilitate project documentation) can be
achieved without having to accept steep learning curve which would
take me away from my primary function and into the realms of
supporting microsoft product knowledge in the work place?