Using DocGen for Salesforce with flows

I need someone who knows DocGen for Salesforce inside and out and how to use Salesforce flows to generate docs to train me on how to setup templates happening through flows. I do not need help with tagging fields or getting DocGen to generate documents from fields on the page. That's a non-issue. I want docgen to bring in the <<next record>> to the next line, etc as I would in a regular mail merge for example. A lot of related records needs to be pulled into the docs, etc.
I am not looking for someone to do the work and deploy it. I need to know how to do it and will pay someone all the hours spent teaching me how and hours afterwards if I need help later on.