Struggling with 4 year olds behaviour

We are really struggling with our 4 year olds behaviour. It is just vile. We have tried to discipline, to reward good behaviour, take toys away, star charts, treats/rewards, naughty step etc but nothing seems to work. It has definitely gotten worse since he had a baby brother but I just don’t know what to do. He gets everything, we both spend lots of one on one time with him, we are constantly trying to understand how he is feeling and why he behaves the way he does. He is very attached to me and tries to hurt his brother whenever he comes near me. He bites me, my husband and even tries to hurt the cat. If we try to punish him (eg by taking something away) he just screams and throws a huge tantrum so we end up spending all night trying to calm him down. He won’t let me and my husband talk, constantly shouting over us if we try to have a conversation. It’s putting a strain on us as we are both just so stressed by the end of the evening. I know that developmentally some of this is normal but I just don’t know what to do. I dread the evenings when I pick him up from nursery and feel so bad on my baby who is exposed to all of this. He doesn’t have any developmental issues and according to nursery gets on fine there. Any advice would be appreciated. Thanks for reading.