A 3 dimensional figure
A 16-sided 3D shape is called a hexadecaheron or a 16-cell. It is one of the six regular polytopes in four-dimensional space, analogous to how a cube is a three-dimensional regular polytope. Each of its faces is a tetrahedron, and it is characterized by having 16 vertices and 32 edges.
It is not clear whether the question means the shape has ten faces of which 4 are square and 6 are not, or 6 faces of which 4 are square. In the first case the shape would be a 16-hedron. The second is impossible.
Xeptagon
Assuming it has 16 triangular sides plus a base making 17 faces in all, it would be a heptadecahedron. If it is a 16-faced shape then a hexadecahedron.Assuming it has 16 triangular sides plus a base making 17 faces in all, it would be a heptadecahedron. If it is a 16-faced shape then a hexadecahedron.Assuming it has 16 triangular sides plus a base making 17 faces in all, it would be a heptadecahedron. If it is a 16-faced shape then a hexadecahedron.Assuming it has 16 triangular sides plus a base making 17 faces in all, it would be a heptadecahedron. If it is a 16-faced shape then a hexadecahedron.
An octagonal prism.
The shape you are describing is a truncated octahedron. A truncated octahedron is a polyhedron with 16 vertices, 24 edges, and 10 faces. It is created by truncating an octahedron by cutting off its corners, resulting in a shape with hexagonal and square faces.
A tetrahedral prism is a three-dimensional geometric shape that has two congruent triangular bases and four congruent lateral faces that are in the shape of triangles. The lateral faces connect the corresponding vertices of the two triangular bases, forming a solid with six faces, eight edges, and four vertices.
An octagonal prism, possibly.
Nonahedron
Two cubes have 12 faces, 24 edges, and 16 vertices.
A 3-D octagon is called an octagonal prism. It is a geometric figure with two parallel and congruent octagonal faces connected by rectangular faces. The octagonal prism has 10 faces, 24 edges, and 16 vertices.
An octagonal pyramid.