This is real stuff but note for those who follow some real guidelines. Don’t just try for 2 days and think you can go outside naked, you will die. Is that a staunch enough disclaimer?
The Wim Hof Method is what it is called. You train yourself with breath techniques, self analysis, and cold hot treatments to be able to control your body to such a point that being outside in freezing temperatures is not a big deal.
I’ve done breath work like this before but for different reasons and I can see through the window of possibility on this. Meaning, my own belief is that yes this is completely doable. But don’t take my word for it! Read about the hundreds of people doing it and learn more about it!