what will happen if someone die who own bitcoin?
Did you happen to sign some paper indicating a beneficiary in case of your death? not!
Does the wallet have any of your actual contact and do they have a lawyer who can go to the home of people who have funds and are inactive for months to know what happened and help? I think not! That's why we need regulation.
The theme you posted is something very complex for the cryptp world and will probably be a headache even for regulators
is their any rules for beneficiary?
No
or anything that can help?
If you have someone reliable, then tell this person your password, private keys and email.