how can i import made skeleton meshes through zbrush to unreal engine and how can i make their animations
You need more than ZBrush to get a character into unreal. Once you have made a character model high poly and low poly, you’d take them to a program like Blender or Maya for rigging and skinning a skeleton and animation work. Then export that to Unreal. Use something like Substance Painter to texture the mesh.
Creating character skeletal meshes like this is a rather long process.