Most of that you can do in photoshop by using shapes and converting to 3d then altering its extrusion for each side of an object. Let me rephrase that, you will need a shape for each side of the object that needs to be converted to 3d and altered each sides extrusion. An extrusion is the thickness of the object's side.
What you can not do or would be difficult to do, is anything organic like the manikin or the bag. If you have time, you may figure out ways to manipulate the shapes required for the object's sides, but that does take time and lots of patients. Those modeling techniques are easier to do in full featured 3d app like blender, lightwave, modo, 3dMax, or maya.
However if it is allowed, you can find free apps for generating human meshes and well meshes already created. Daz3d would be a good place to start for that, but since this a school project, its up to your teacher.