A triangular pyramid.
triangular prisom
Triangular Prism
There is no 3D shape with 6 faces: 4 rectangles and 2 triangles. See the link for all forms of hexahedra.
A cuboid.
A butt
Cuboid
cube
A 3D shape with all triangular faces can be a tetrahedron pyramid.
it is called a triangular prism
a hexagonal prism
An icosahedron.
A cuboid.