This means there is no up front fee, no subscription, no insurance requirements. Someone with no money or bank account should be able to receive non-emergency care without needing to pay.
edit 4 Jan 22: This refers to those currently eligible as of 4 Jan '22. If there is a substantial change (judged by me) in the eligibility criteria such that proportionally many fewer people are covered, I might resolve it as 'no'.
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@Odoacre I will use the definition currently on wikipedia, which was what I already had on mind:
"The vast majority of NHS services are free at the point of use.
This means that people generally do not pay anything for their doctor visits, nursing services, surgical procedures or appliances, consumables such as medications and bandages, plasters, medical tests, and investigations, x-rays, CT or MRI scans or other diagnostic services. Hospital inpatient and outpatient services are free, both medical and mental health services. Funding for these services is provided through general taxation and not a specific tax."