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How to control bullets in Ribbon Versions of Word by Shauna Kelly
That is the easy part. Disabling the ribbon buttons is harder.
For yourself or for your templates/documents or for your office in general?
For yourself using the Word interface, you are pretty much limited to removing that entire group from the Ribbon.
Not using the Word Interface through XML is doable, but not a beginner's project.
Using those methods, you can make changes that can only be in certain documents/templates, changes that are in yourr own system only, or global changes for an office or business. Look forward to a major investment of time, though unless you are already a programmer.