A line is perpendicular if it meets at 90o.
A polygon with 4 sides has 4 angles. All polyhedra have at least 4 vertices so I cannot think of any shape that meets the requirements.
4 angles
None normally but in the form of a rectangle it will have 4 right angles
No because they will form 4 right angles of 90 degrees
yes, it has 4 right angles and 4 sides
There is no quadrilateral that meets these requirements. It is, of course, possible for a pentagon (or polygons with 6 or more sides) to have 4 equal sides and only 2 right angles.
Not normally but in the form of a rectangle it does
The sides if a square or rectangle?
Yes providing the 4 interior angles add up to 360 degrees
yes if it is a square. squares are rectangles with their 4 sides and 4 right angles, but rectangles are not squares without 4 equal sides
perpendicular