Help please

I am 1 week PP with my second child. I have a 2.5 yr old son who has always been a little crazy at time. I was layed up in the hospital for 3 days after having the baby and since coming home have been doing thinks I can given the restrictions in place after my c-section/ tubes tied.

My husband has been wrangling our son for the most part, I do what I can for him but just not the lifting him, while nursing the baby. My husband is not handling the transition from 1 to 2 very well is and is constantly yelling at our son for things he has normally done without getting yelled at for. Our son is at the picky not wanting to eat phase which I talked to our pediatrician about when we did our daughters intake appointment. She told us its completely normal and just keep offering food and he will eat when he wants just give him time. Our baby on the other hand screams when my husband holds her and kicks when he tries to change her and he feels like she hates him. I tell him he needs to just hold her and talk to her and just give it time. He is afraid he is going to break her since shes so small.

How do I get him to calm down with our son and get him to help alittle with the baby so I can go to the bathroom, shower or even nap without everyone losing their shit