you call a two dimensional shape with six sides a hexagon
vertex
When two sides (called faces) of a 3-dimensional shape meet, they meet at an edge.
A shape that has 10 sides (two dimensional) is called a decagon. A shape that has 10 faces (three dimensional) is call a decahedron.
A shape with 7 sides is a heptagon
A shape with three sides is a triangle.
It could be a cylinder
Triangle is a shape with three sides.
A shape with 8 sides is an octagon.
A regular shape.
There are infinitely many such shapes. A polygon with 4 or more sides can have two sides that are parallel and they need not be the same length.
a shape with nine sides is called nonagon