If you have a script that you’re confident is putting into competition, then you can send it to all sorts of places - agents, managers, studios (to a limited degree). There are all sorts of resources online to help you with your game plan. The best approach, however, is to be in L.A. and get your script to people in the know. Of course, make sure you have material that you can stand behind with confidence. When you have material that you are 100% happy with, don’t you find ways to get it into peoples’ hands?
P.S. I made a damn sight more than 45 videos before I was 17. I made more than that before I was 14. It’s called “being a kid with a camera”. Best way to learn, regardless of your age.