Family Issues

I live with my dad and my sister and the relationship dynamic in the house has grown quite toxic over the years. My sister and dad do not get along at all and either fight, put up with each other or don't speak at all. I have a lot of resentment towards my dad which leads me to try and avoid him as much as possible which is not entirely healthy either. Out of the three of us, I don't think any of us are good communicators. My dad leans towards agressive communication that always puts himself as the victim. My sister can be assertive and outspoken but most of the time when she talks to my dad she ends up angry and can't put up with it so she might lash out, walk away from the fight (because she needs space), or she'll be passive agressive. My communication style is to try and avoid conflict but that can be difficult with my dad especially if he is asking me for an opinion that he won't want to hear. It is extremely frustrating to talk to someone who asks for your opinion but gets angry when you say it or who thinks your opinions are ignorant. I honestly don't know if we're all equally toxic or if one person is more toxic than the others. Me and my sister have a similar opinion on our dad although I try to understand the reasons for my dad's behaviour more than my sister does. It would be ideal if we could get along but as a result of feeling resentful and distant for so long I now feel quite detached from him and I don't know how I would build back the relationship. Which is quite sad to think about and possibly could have been avoided if I'd had better communication skills earlier. I think the three of us probably all need individual therapy to address things but my sister is stubborn and I think when she moves out she'll probably just cut my dad off and my dad mostly thinks my sister is the problem but rarely takes accountability for his own actions.