At the risk of being a wet blanket on your creative urges, here's the plain truth. Just in the US alone more than 30,000 screenplays are written and registered in a year. A handful get produced. Most are written by pros already in the industry, the rest by a combination of folks who know people who know people who can get a 'greenlight', and some very aggressive ordinary people who devote themselves to the intensive promotion work needed to getting their work produced. I have heard actual numbers quoted that new (GOOD) writers are on average getting a production of their EIGHTH script. This is not 8th draft, this is a polished 3rd or 4th or 12th draft of their eighth screenplay.   This represents several years of work for most mortals.

Unless you are employed as poolboy to a star and have unusual access to people who can make things happen, you will lose many years of your life to perfecting your craft and then to pushy selling of your work product. If by some chance you do break in, you will then compete in a vicious industry to keep getting productions, and pushing against having your work being torn to bits by producers and rewriters before it gets to the theaters.

If that's really how you want to spend your time, good luck to you. I think a lifetime is better spent with friends and music, myself.