You ask the question as if there were only one possible answer. This is not at all the case, but one example of such a shape is a cube. The unit cell of the triclinic crystal system is another, and there are even less symmetric possibilities (for example, there's nothing in your description requiring the opposite faces to be parallel), but I can't think of any simple name to give them.
to use your IQ to solve every problem
cube!
6 faces, 12 edges
A cuboid seems to fit the given description because it has 6 faces, 12 edges and 8 vertices.
That 3D shape is called triangular pyramid.
A 3D 5 sided shape is called a dodecahedron. It is a solid with 20 vertices, 30 edges and 12 equal pentagonal triangular faces.
It has 12 edges and 6 faces
a cube
A hexagonal prism.
a cube or cuboid
According to Euler none; for all 3d shapes: Vertices + Faces = Edges + 2 ⇒ 12 + 8 = 19 + 2 ⇒ 20 = 21 So unless 20 does equal 21, no 3d shape has 8 faces, 19 edges and 12 vertices. Any 3d shape with 8 faces would be an octahedron.
Hexagonal prism
cube!
a square
It is a cuboid
A cube or a cuboid could have 12 edges, 8 vertices, and 6 faces.
i would say a cube
A hexagon based pyramid.