What does this mean - re ACA?

[TlalocW]

Undocumented immigrants can't get Marketplace health coverage. They may apply for coverage on behalf of documented individuals.

I'm in an argument with a guy about the government shutting down, and I know he's misinterpreting this, but I'm not sure I get it.

[DURHAM D]

1. There is nothing to get.

Stop talking to stupid.

[W_HAMILTON]

2. Probably means an undocumented parent can apply for coverage for their child that was born here a citizen.

Sounds like he's another MAGA fascist that wants to do away with the parts of the Constitution he and his cult leader no longer approve of.

[Silent Type]

3. They can apply on behalf of eligible children or adults living in house. But they are just filling out forms.

[haele]

4. You need a valid social security number to get SS Benefits, Medicare, Medicaid, or sign up for the ACA.

What MAGA and the GOP scare mongers are trying to say is that undocumented immigrants get an I-90 number to act as a temp identification number for any long-term visas they might become eligible for on their way to getting a hearing or green card, and they're using that number to get benefits.
But if they have the number to be able to get the benefits, they and their status is now documented.
As it is, they - and every other person in the US, no matter how they're here, are entitled to ER services, or any private services a charity might give them, like housing or a job or something like that. But they aren't going to get anything that comes from Federal money. Because unless the SSN is present, and now a birth certificate and all other sorts of verification that's been required since 2010 at least, they aren't getting anything.
Whatever a charity gives them is the business of that charity. And if the MAGA is going to get all "well, I can't get that sort of service", maybe they should go to another country and hook up with an immigrant charity to get those services. Or bug their congress critters to expand health care and address things that hurt citizens like lack of current job training, affordable housing and utilities, or problems with food insecurity.