What occurs in case a parent passes away without a will? Are the children entitled to the share of the house of the dead parent.

My mother passed away, and there was a name of both parents on the house. The house is named after her, but I do not know whether it is on the mortgage. Does my father have the power to force us, family-grown adults, out of the family home or is it her grown children who own a share of the house. He would have to buy us out. Correct?