That's a very broad question and the forum is more about detail issues. However, we will try to point you in the right direction.
Do you mean
- Context Sensitive Help generatly
- Dynamic User-Centric Help OR
- Dynamic Content Filtering?
Context sensitive help is a matter for your developers that might involve you depending on how they want it done. (Map IDs or URLs). There is information about calling help on my site.
For the other two, see the RoboHelp Tour and search on Dynamic. Dynamic Content Filtering is also covered in the sample projects that ship with RoboHelp. It is used in Responsive layouts whereas Dynamic User-Centric Help is used in WebHelp.
Plus of course they are all covered in RoboHelp's own online help.
See www.grainge.org for free RoboHelp and Authoring information.

@petergrainge
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