Start with Customize the Ribbon by Greg Maxey.
I agree with John that you want to utilize both Workgroup Templates and the StartUp Folder.
Any macros being called must be in attached or loaded template files at the time the call is made. Generally, my preference is to have the macros be in the template holding the Ribbon modifications. That simplifies things.
Any macro outside of that template must have a unique name and be public.
In addition to a custom ribbon tab or two, you can include QAT modifications in your template that will be available when it is loaded as a global template. .
https://addbalance.com/word/QATmodification.htm#PageStart
I keep such templates in a network location and update local copies (in the Startup Folder) as a part of the network login. I do the same with the Workgroup Templates using the old XCOPY DOS command.