https://www.greatbigstory.com/stories/the-ultimate-polyglot-this-man-speaks-32-languages
https://www.worldcrunch.com/culture-society/hyper-polyglot-greek-translator-speaks-32-languages
For him it is all about getting immersed and absorbing the foreign culture - even to the point that he changes religion and eating habits according to his current projects.According to what I've read, He learned through total immersion without ever doing a formal study!