This is a small video showing some hints on how to update a widget with C++ in Unreal Engine 4.
There are other ways of doing so, this is one with a low compromise when you are working in a large team with other people taking care of UI while you do the code work.
The course link at Udemy.com I have mentioned is from Tom Looman and found here: https://www.udemy.com/unrealengine-cpp/
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