I'm sorry that you're going through this right now. Remember that he's human and maybe he's just not sure how to deal with the anger he's feeling from his job and the possible separation from your mom. Not an excuse for treating you poorly, and you shouldn't have to tiptoe around him, but a little understanding goes a long way. Maybe when you see that he's in an aggravated mood, instead of trying to help him, since maybe he just wants to do whatever alone, you can just go to your room and let him blow of his steam on his own instead of putting yourself in the line of fire.

I know none of this is fair. He shouldn't take his emotions out on you, these are just suggestions to stay out of the line of fire while your family is going through this rough time. I imagine he has a lot of emotions he's dealing with right now, with both his kids still living at home, because one is disabled (I don't know the deal with your brother) and mom maybe leaving, and didn't he just lose his job recently (although sounds like he got a new job).

I know he yelled at you to help, so maybe next time just ask him specifically what he wants you to do.

I often help out with chores when I go to stay at my mom's and I don't know where everything goes, I just put away everything that I know where it goes, and leave the rest on the counter and ask her or my dad to show me where they keep it so I don't have to ask next time. Usually they appreciate that I did the cleaning and that all they have to do is show me where to put a few tupperware plates or whatever.

Sorry you're going through this right now.

Seesaw