How to deal with an 8 year old daughters BIG emotions, particularly anger. I’m scared for puberty! It’s affecting the whole household

Be understanding. Don't dismiss her feelings or think of her as being dramatic. Let her know you're there and her and you support her. Take her out one on one. Watch a movie with her. Talk to her about how she's feeling. It's hard for girls as people tend to fob them off as emotional and difficult when in reality they just want someone to actually care about how they're feeling.