A three-dimensional shape with eight triangular faces is called an octahedron.
A solid figure with eight vertices and all faces of equal size is called a cube. Each face of a cube is a square, and a cube has 8 vertices and 6 faces.
Triangular prism
A triangular prism.
A triangular prism.
triangular octoprism
A triangular prism has 2 triangular faces and 3 rectangular faces.
triangular pyramid
A triangular based pyramid would seem to fit the given description which has 4 equal sided triangular faces, 6 edges and 4 vertices.
A triangular prism.
A Triangular Prism
Four triangular faces.