We moved to Portugal from the UK three years ago. Any resident can use the national health service (SNS), regardless of whether they pay social security or not (we do as we both work). There are very small co-payments in the SNS (a GP appointment is 4,50€ in my village). There are 24 hour health centres which you can use if you need to see a doctor urgently. You turn up and queue, and it costs 14€. This means A&E is actually just for accidents and emergencies.
There's also now an SNS app which has details of all your vaccinations, through which I think you can book video appointments, but I've never tried it.
Health insurance is quite cheap, so we generally go private. My policy costs around 500€ per year and covers 80-90% of the cost of consultations, tests etc, depending on whether the provider is in or out of the insurance network. Co-payments for private consultations or GP appointments are around 15€.
My partner has to use the SNS for a pre-existing condition, and has very good care.
By EU standards we're a poor country, so healthcare isn't perfect, but we're very happy with it so far. There are issues with funding the SNS which are a big political football - incomes are low on average, and although taxes and social security are higher than the UK, there's a lot of tax avoidance.