If it is Word you need, please take a look at my demo project. Most things you would like to do to manipulate your existing word doc with data coming from a Mendix app are catered for and it’s free to use.

You will need to provide this functionality with some java actions and the POI library. There is no direct option to perfrom this action in Mendix. There are however quite a few word related modules available in the merketplace that might help you inachieving what you exactly need or at least provide you with some ideas on how to start building this functionality.