A calf can get calf starter a few days after he's born. Some like to hold back until a few weeks prior to weaning.
This is a very cruel question, but I'll answer it anyway. If you want to kill a calf, then starve it to death. You're not going to kill a calf by feeding it too much, unless you want to have it die...
every 8 hours.
Once every two or three hours, just like any baby mammal.
Usually after a few days after birth.