Father won't make any decisions

My 77yo dad is totally stonewalling me on end-of-life prep. My Mom/Stepdad have a "death binder" and prepaid cremation ready to go, but my dad has... nothing.

The mess:

• The Will: One typed page from the 90s. Valid, but bare bones.
• Zero Paperwork: No POA, no DNR, no medical directive.
• The Assets: He won't even write down his account info or passwords.
• The "Plan": He says "it would be nice to be buried above ground." He’s broke and we have no family vault, so this is pure fantasy and frankly ludicrous

If he doesn't make a call, I’m doing direct cremation and a Celebration of Life later because I can't stand traditional funerals.

How do I get a stubborn, broke parent to face reality and at least sign a POA before it's too late? Any advice on getting a "list of accounts" out of someone who thinks they’re immortal?