I need your advice.

So in our childhood, me and my brother lacked the attention of our parents. It wasn't their fault too. My dad worked hard and till late for us. And mom was too busy in chores to pay proper attention to us. And we both had bad relationship and very big gap between us and our dad. But i took my chance improved it. I realised it someone had to do it. But the relationship between my dad and brother countinue to be more apart. Mind you I'm a teen and he is grown adult, 22 years old this year. My brother has anger issues. No matter what and how much my parents (especially my mother) cooperates with him, he doesn't listen. Hes addicted to phone, and anime. He has failed 2 semester by now. And still watches anime excessively even tho mom and dad says to do it in control. Like they're THAT understanding. My brother screams at my mother and dad when in a an argument. And i hate it. I don't care if he does and lives. All I want him to be a nice son and human being. But i hate it when he screams at my mother. Don't even say sorry. And me? I had such issues too back 2 years back. But i realised it and improved. I've had MANY addictions, but i came over it. IT WASNT EASY. For myself i didn't wanted to but for my parents who sacrificed everything for me, i wanted to, and still doing. But why isn't he? He is someone with severe addiction and has short temper. How do I protect my mother and help him solving his issue as a sister(caus in the process i don't want to cross my boundaries).