I am looking to create an Online Help that looks similar to the graphic attached. Can someone advise me as to the best approach I might take?

Thank you!

Thank you!
The responsive layouts in RoboHelp 2015 are HTML5, as are the multiscreen layouts. The responsive layouts are much easier to work with.
The layout you show will almost certainly be something Google has created in-house but it is very similar to the layouts that ship with RoboHelp. I suggest you try one of the supplied layouts and then come back saying specifically how it is not what you want, if that is the case.
When you have generated a layout, keep resizing the window to see how it morphs as you reduce the size to mimic a tablet and a smartphone.
See www.grainge.org for RoboHelp and Authoring tips

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