Is there a way to add widgets to a horizontal box widget?

I am trying to make a card game and i represented the board with a box i want to add cards to that box is it possible or do i have to make them invisible by default and make the visible when i need them to show?

yes it is possible you would just need to add the new widget as a child of the horizontal box which would requiring you to have a reference to the box component.

below is a example