I‘ve been doing Wim Hof Method stuff for about 2 years now (some times more consistently than others...), and it really helps me with getting my life together. I purchased the Fundamentals course, which has helped to get more into it. But just starting with what’s out there for free is quite sufficient I think. https://www.wimhofmethod.com/
Cold immersion feels great, there’s definitely a mood boost each time I come out of the cold, and it is really motivating to look back and see how much easier I can handle the cold. Also the breathing techniques is an effective intro to Pranayama and great for managing low energy.