What is the name of the three dimensional object with 4 sides, each side has three edges and three corners?
It is not a pyramid. A pyramid has 5 sides, 4 sides are triangles and the base, or fifth side is a square.
It is a tetrahedron ( tetra is a Greek prefix meaning 4 ). It is in the polyhedron family. A triangular prism is and elonged triangle that is not distorted, so that you have a triangle at both ends.
So that you have a triangle at both ends and three quadrangles on each side.