My brother hits me and idk what to do

I’m turning 16(F) in November and my brother recently turned 19, since childhood I’ve grown up being beaten up by him or being hit by him, I joke around it to cope because it’s normal but the thing I still get beaten up by him, im around 45-50kgs, he’s 70-80kgs, he still hits me, and it hurts so bad, we got into an argument and he threw his heavy iPhone on near my chest and rib cage, pain like pulsed through my skin, he gets so violent? Like Ik older brothers are rough but it’s terrifying, i tell my parents and they yell at him and try to help me but his anger is so violent, we got into an argument and he did that and idk what to do. He has a lot of narcissistic traits, my chest hurt so much, and we were over at my cousins, everyone heard me it hurt so bad. I feel guilty idk why, but I hate him so much, he’s nice to me sometimes but most of the time he’s like this. It’s so scary idk what to do. How do I tell if he’s rough or violent??