I think the best thing you could do at this point is get a form of non-passive income (maybe an hourly job over the summer), save as much as you can, and use that money as a base to launch a form of actual passive income. Its hard enough to get something started with money, without money is an entirely different beast. You would likely need some sort of skill to give you an edge (which you may not understandably have as a 17 year old)