It would potentially be something more like the US where your level of care is heavily dependent on what you can afford. The US is pursuing full market access for their pharmaceutical companies - who are notorious for their price gouging tactics - and the UK is in a pretty weak position post-Brexit. There's a reasonable likelihood that UK health spending will sky-rocket while patient outcomes plummet.
No, they mean something like England already has for dentistry or social care or opticians - access is available if you pay for it, and not much available if you can't pay for it.
Sounds like what we have already! Given OP's choice of words ("two-tier"), it brought to mind something more like the European system.