https://support.apple.com/en-us/HT208510

First result after searching “apple id deceased relative”

Apple accounts are notoriously hard to gain access to if the user hasn’t taken the time to manage their security questions and/or delegate others to have access in dire circumstances. I highly encourage everyone to take a few minutes to designate someone and make sure security phrases etc are all in order. Losing access to the account could mean lost access to critical documents and memories (depending on how you use iCloud) forever.

Luckily we knew a pc password that let us get to their email. From there we reset the password.

Just so you know, power of attorney becomes void at death. It allows you to act as that individual, but when they are deceased, you can’t act as them anymore.

If you run into other items, just be aware additional documentation will very likely be needed—death certificate plus typically letters of testamentary/administration (the term varies by state).

Source: I worked with estates, trusts, POAs, and more in a banking role for several years.

If they did not setup Legacy contacts (people who can access their account after their death), you will need to either gain access by resetting passwords, or via court order.

The attorney handling the probate might help you, or you can try the legal aids that work with that courthouse.

And as an aside, don't forget to setup your own legacy contacts now and possibly get your parents to do it now. Having gone through this a couple times recently, it was very nice to have the legacy contact access. Made everything simple.