All I will say is this:

I'm assuming OP wants to be an actor, so I will cater this towards that.

Being an actor is tough as hell...if you don't already come from money.

No one in Hollywood gives a flying **** about your talent. No one cares, only because everyone here is doing the same thing. However if you're really insistent, the following steps might take you in a good direction:

1. Get some headshots
2. Don't be afraid to do student films, and don't be afraid to do them for free. You never know when you'll hit the jackpot and work with someone that actually turns out to be a somebody. In the meantime, use these films to build your reel and find an agent. How do you find student films to act in? Well assuming you live in Los Angeles, lacasting.com is a great place to start.
3. Actively look for representation. Do you research on them. Agents and managers work for you, not the other way around, but at the same time keep your ego in check.
4. If you can't take rejection, don't even bother. nine times out of ten, you will be rejected. Like someone else said here, casting calls are like a cattle call. Hundreds of thousands of people are submitted to a casting call. Only about 30 (Give or take) will get seen. About 10 (varies) will get a callback. Only one will actually book it.
5. Your talent carries less than 20% of the final decision when casting. Studio heads, casting directors, directors, producers, financiers, etc etc etc all have a say. Just because you know one director, or one producer, doesn't mean they can pull those strings for you.

I'll break television casting down because this is where I specialize the most: 1. Script broken down. Characters need to be cast. 2. Casting call sent out. Your agent with submit you, you'll get called in...maybe. 3. Go in, do your thing. 4. Casting director filters out who they believe can play the role. 5. Call back. Do your thing..again. 6. Tapes get sent to the director/producer, whoever initially wants them. It can vary from show to show. Typically it gets sent to everyone, and everyone has a say in who they want. 7. Producers session. You'll meet the producers if you're one of the maybe three they choose are best to fill the role. 8. Studio session. You'll go to the studio, meet the studio heads, or whoever is in charge. From there, you'll finally be cast...if they think you're right.

Like I said before, talent means almost shit. Most of the time it's about your look and if you're likable. In reality, most casting sessions are a meet and greet. The people who can act will make it to a callback. The people who can't get filtered out. If the casting director loves a look so much, but the actor can't act, they'll maybe still see them for a callback. Sometimes they'll make it as far the network. Hell, sometimes they'll be cast.

It's a brutal industry that has a lot of ego and a lot of butthurt people. Everyone thinks they're better than everyone else. If you think you can handle constant bashing and criticism, by all means give it a try. If you're broke, I suggest you don't. If you think you can get a part time day job and still go to auditions, think twice. Unless your part time day job is flexible and will let you walk out to go to an audition, you'll have to have another source of income.

On a brighter note, you can't book a job if you don't try. You can't be successful unless you are headstrong and proactive about your career.

Any more questions and anyone is free to ask. PM or not.

TLDR: The industry sucks big balls. Avoid it if you can.