Hello
@Crobbins
Sorry to read that your Dad is yelling at the staff. It's upsetting when a loved one seems so distressed, As
@Bunpoots mentioned, it could be that he is still settling in if he has not been there long.
My mum has often shouted and screamed, threatened staff and I'm afraid sometimes inflicted minor injuries. The staff at your Dad's nursing home will hopefully be looking for triggers (personal care is often a trigger for aggression, for example) and seeing if they can do things in a different way or at different times. They should also be looking for signs of infection, particularly urine infection, although it can be difficult to get a urine sample if someone is very agitated. They should also be looking for signs that he is in pain, which can also cause aggression. It could be that your Dad needs a review of his medication to address anxiety/aggression, so it is worth asking about that.
If it's a sudden change in behaviour, infection is a likely cause so worth checking out.