Good mountain rescuers have many years of high-altitude cold weather mountaineering experience. You are a mountaineer first and a rescuer second. Join a volunteer mountain rescue team. Contact the local sheriff to ask about teams in a particular area, or search the world wide web. Quite frequently, you can attend a college or university in a mountainous region that has a mountain rescue team,gaining valuable experience while getting your education.
Mountain rescue is something that requires talent that is acquired over years.
You can not take a 3-month course and be set to save the world despite what some organizations will tell you about their training. The volunteer mountain rescue teams in Colorado, including RMRG, do not and most likely will never charge for services. There have been some cases where a few county sheriffs have charged for SAR operation. The Boulder County Sheriff has not and does not plan to charge victims of search and rescues. See the next question.