Nich was one of my classmates in Med school. He’s a teacher, now, and making some killer videos. Everything advanced is based on deep foundation. This is a great overview, it touches on the parts that often go unmentioned without getting bogged down in too much detail as to lose the big picture. May not be able to follow all of this (and his other videos will be more challenging) - but it’s worth a watch if you’re interested in this kinda stuff.