Legal Question in Wills and Trusts in California

Yes to the first part of your question, once an executor is appointed by the court and the will has been admitted to probate, Letters Testamentary are issued. The executor then has the duty to marshall all assets which means that the bank accounts, securities and other assets are transferred into the name of the estate - and the new estate's taxpayer identification number is used - and maintained to pay creditors and distribute.

With full IAEA powers, there are certain things that can without court supervision, distribution to the beneficiaries named under the will is NOT one of those powers. You have to petition the court showing that all notices have been given, the status of all creditor's claims, the payment of taxes and other debts and then seek court approval for distribution. Only after you have received an order from the court approving the distribution, do you distribute the assets to the beneficiaries under the will.

You mention life insurance, the executor only has the authority over life insurance proceeds if the estate is named as the beneficiary or there is no beneficiary named. Otherwise, the beneficiary listed on a beneficiary designation has the authority to communicate with the life insurance company.