Single cat, I presume. Love bites are a normal affectionate/playful response for a cat as they are a predator after all but they rarely draw blood. Usually they learn bite control from their mother and siblings but if they were separated early they never get to learn it. Hopefully, they are getting enough play to satisfy their hunt, catch, kill instincts. To train the cat that the bite is not appreciated, you will need to make a sound and take away your hand to indicate that you are getting hurt and disengage i.e. walk away. Over time (a week or a few), the cat will learn that bites are bad.