How to bind onclick event to UMG?

now i meet another problemmay be you can give me some suggestion!
i am making a card game. there is a 3D person in level,and i will create a widget ,so it seems the 3D person is part of widget,that what i want. However the 3D person can not transparent from image of widget. now i want to image only to be background of 3D person. =.=need your ideal
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