How do I transfer property ownership after my father's death without a will?

Since your father died intestate (without a will), his property will be distributed among the legal heirs according to the succession rules applicable under his personal law. For the house (immovable property), you and your siblings would typically first obtain a legal heir certificate or, for a more comprehensive and legally robust process, pursue a succession certificate or letters of administration, depending on your specific situation and any disputes among heirs.

For the property itself, once heirship is established, you can either get it mutated in all heirs' names jointly and continue holding it together, or execute a partition or release deed among yourselves if you want to divide it or have one sibling take sole ownership.

For the bank accounts, a succession certificate is generally what banks require before releasing funds to the legal heirs, especially where there's no nominee, or the amount is significant. Given multiple heirs and different asset types are involved here, it would be worthwhile consulting a lawyer to map out the most efficient sequence of steps for your specific family situation.