A shape with 5 angles has 5 sides, always. Pentagons have 5 sides, and 5 angles.
A shape with 5 sides and 5 angles is a pentagon.
A shape with five sides would be a pentagon, but a shape can not have 5 right angles. Squares and Rectangles are both shapes with 4 sides and 4 right angles. They are the only shape with the same amount of right angles as there is sides.
That is the pentagon
It is a pentagon
A polygon with 5 angles and 5 sides.