The Week has an article titled Bernie Sanders and the rise of American social democracy.
Let me start with a bit of history. Social democracy developed out of a turn-of-the-century split from traditional Marxists, who had long thought a political revolution would be necessary to replace capitalism. Social democrats, by contrast, thought the same egalitarian objectives could be evolved over time through parliamentary democracy and without suddenly overturning bourgeois institutions of private property. (These definitions tend to fray at the edges, but that’s a fair gloss.)
This is a good explanation of how things work in the Nordic countries that have highly productive economies and great social programs.
Let’s not get too hung up on labels or examples, though. Whatever Bernie may label himself as, look at the programs and policies he supports. Decide for yourself if these are things you want for the USA. If they are, support Bernie Sanders because he supports what you want.
Don’t get hung up on some program in some other country that you assume Bernie supports because the labels in the two countries seem similar. Bernie is quite happy to tell you what he supports and what he doesn’t. That is what is important. If you are not sure about Bernie’s attitude on some policy, try to find out what he says and does about it. Don’t think you can read his mind because of a label.