Pet Care Needed

My 1-year-old Siamese cat keeps play fighting with my other cat way too aggressively. My other cat will screen loudly because my Siamese bites him hard when playing. Siamese will also always try to rush and eat my others cats food when it automatically dispenses. Siamese also tries to go potty in my other cats litterbox. Both cats have their own water/food bowls as well as their own litterbox