They must have all angles which are the same, all of whose straight lines are in the same ratio and whose curves have radii of curvature in the same ratio.
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They are closed 2-D shapes with straight sides.
3-d shapes are not made from 2-d shapes. 3-d shapes may have projections onto a plane that are 2-d.
There is Paper or Card or some other art stuff you have in your home
a cube has parallel faces so does a cuboid and so does a cylinder and also if you want to find out lots more stuff about 3-D shapes or 2-D shapes see the website in the related link
3 dimensional shapes have breadth, width and depth whereas 2 dimensional shapes have only breadth and width