I tried to bake normals from high poly to low poly and it has no resault, only broken normal map. I watched so many videos about, did the same or tried change Max Ray Distanse/Extrusion and still have troubles. I added screenshots with high poly, low poly(with normal map) and baking settings
Link for .blend file: https://www.dropbox.com/s/rruk0aqj7wdgkek/test.blend?dl=0