Alice, we get this in here a lot. And us regulars just rooooooooll our eyes everytime we see it. Because there are literally a million wannabe actors here. And we see it at least ten times a day.
Want to know how people get "discovered"? It doesn't just happen overnight:
1. Go as much experience as you can. That means practice, practice, practice, every day. Most people don't have the discipline to be any good. And this also means that you sign up for every singing workshop, musical theater production, and drama/singing camp that you can find. There's no such thing as an overnight success here. People who succeed have been doing workshops since they were five.
2. Next, you need contacts. By doing step 1, you'll start to get contacts. You need them in this town. Because the way you get a contract is when someone in the music or movie business hears about you. And they aren't going to sit in every karaoke bar in Hollywood to find you. (It's too painful, much like the opening rounds of American Idol).
3. You need an agent. Because your agent will have your demo, your head shot, and he/she's the one with contacts in this industry. Your agent is the one that gets the casting calls. Your agent can set up the gigs in the really high profile places.
4. You need money. Money to stay in LA while all this is going on. Money for workshops, camps, and classes while you improve your craft. Let's do the math, shall we?
Unless you have mad skills and a killer resume, you'll make minimum wage, which is currently $8 per hour. If you are lucky enough to get 40 hours per week, that's 320 per week, or $1280 gross per month. And that's BEFORE taxes. Take home is probably $910. Now it's a hard economic fact that you should spend around 1/3 of your salary on rent or mortgage. One third of $910 is about $300, which is what you can afford. However, the average rent for a studio/bachelor/single apartment is about $1000, and a 1BR is about $1200. In order to afford that, you need to make at least $3000 per month. And since you need a car, you'll need about $100 per month for auto insurance. Utilities vary from place to place, but you can figure $150 per month for that. You'll need a cell phone, so your agent can contact you: Another $50-$100 per month. Food varies, but figure about $500 per month.
Don't they have a class in jr. High where you do this?
If you wanted help, you got the best advice anyone can give you at this point. What you choose to do with it is up to you.