Thank you for answering my question. I have played with the Layout options but seems it only works to adjust the HBoxContainer alignment to its parent node. I can not get it to work on its child nodes.
If I put another HBoxContainer (or other container in general) in side the a HBoxContainer, then the child node's Layout option is disable. Since all size and other position are disable for child nodes inside a HBoxContainer. I haven't find a way to adjust the alignment of the child nodes, so is that a way I could arrange the layout a child nodes, and get the child nodes of a HBoxContainer horizontally align.
A simple diagram for intended result