you could use wax, and dye for the wax, this would probably look the most real and require most work and experience (e.g. look at Tussauds wax figures). Probably easier would be to make the figure out of something like plaster and then paint it with acrylics. depending on your painting skills it could look very real.
Latex is a substance which can look like skin, look at latex masks to get an impression. But it's not going to be easy either. Also I am not sure what paints are good to use.
Making something look very real requires a lot of practice. But you could also look at Ron Mueck's work, he makes extremely realistic looking people (though often different scale). I think he uses silicone rubber and acrylic paint for at least some of his work, but you can research what he uses.