[help] How create a widget blueprint dynamically and add it to a scrollbox?

Hello everyone, I hope to get your help and advices about my puzzle:

I made a blueprint named “DramaSingleWidgetBlueprint” as follow:

https://forums.unrealengine.com/attachment.php?attachmentid=115645&d=1477832087

it contains a button, a text and a spacer, maybe other else.

I want to create one of it (or a large number of ) dynamically in CPP program,
and add it (or them) to a scroll box as follow:

https://forums.unrealengine.com/attachment.php?attachmentid=115646&d=1477832099

I am a complete beginner to UE4 and An experienced C++ programmer.

What should I do for that ?

Thank you very much for your help.