There is no polygonal shape which has exactly those angles. It is possible for a concave polygon with 6 or more vertices to have the given angles.
a shape with 7 vertices
A square, rectangle.
Depends on the shape. A right triangle has one right angle, a rectangle has 4, an equilateral triangle has none, a circle has no angles. There are polygons with more than 4 right angles, and there is no limit on how many, but those with more than 4 are not convex.
The number of vertices does not determine the number of faces. If the shape with 6 vertices was a quadrilateral based bipyramid, it would have 8 faces. A hexagonal based pyramid has 7 vertices and 7 faces. So more vertices does not necessarily imply more faces.
A star is not a specific shape: it is a generic word for a shape which has an even number of vertices. The interior angles at alternate vertices are usually reflex angles. A star can have six or more vertices.
There is no polygonal shape which has exactly those angles. It is possible for a concave polygon with 6 or more vertices to have the given angles.
Any shape with two or more vertices can have one or more pairs of equal angles. The simplest of these is a symmetric lenticular shape with just two vertices.
There is no polygonal shape which has exactly those angles. It is possible for a concave polygon with 6 or more vertices to have the given angles.
If the question is about a plane shape with exactly 3 right angles it could be an irregular polygon of 5 or more sides. If the shape can have more than 3 right angles then a square or rectangle are also possible. Finally, in 3 or more dimensions, a polyhedron with any number of faces can have 3 or more right angles.
The simplest shape that can have 2 right angles is a rectangle or a square. You can make an unlimited number of more complex shapes, though. A house shape is a pentagon with 2 right angles--you could even make it with 3 right angles.
A shape with four sides has four vertices and a shape with three sides has three vertices, so a shape with four sides has more vertices than a shape with three sides.
a shape with 7 vertices
A square, rectangle.
Depends on the shape. A right triangle has one right angle, a rectangle has 4, an equilateral triangle has none, a circle has no angles. There are polygons with more than 4 right angles, and there is no limit on how many, but those with more than 4 are not convex.
A shape with more than four sides, but has four right angles. There is no name for it.
The number of vertices does not determine the number of faces. If the shape with 6 vertices was a quadrilateral based bipyramid, it would have 8 faces. A hexagonal based pyramid has 7 vertices and 7 faces. So more vertices does not necessarily imply more faces.