I switched to game development in 32, when it has been 12 years of design and development. It is in our company there are those who are 18.
Unity has mastered a month before the level when you can do your little game.
This is what I?
1. To work as a developer in a game company, and you want to program and know the theory, or simply not pass the interview. To understand the engine is not enough. And to be cool by the developer at a cool company: time
2. To work as an artist, animator, designer, we need skill and portfolio. A few years of hard work. The June pay very little.
3. To come up with game mechanics, concepts, need experience in either game development or other projects with game mechanics. In the producers, and game designers it is possible to retrain from the grocery store or project managers. That is, you need experience of team management, solving business problems (startup, monetization, improving conversion and so on). As I understand, this is also the years of work.
In the end, if you want to deal with thinking through games, the easiest way is:
0. To view on YouTube videos on the subject of game development, occupational choices, about game design and producers. Spend a couple weeks on study topics.
1. To learn the Unity engine to develop your project (design, development, sound, animations and do everything else yourself), one of the best courses for beginners in English
2. Releasing it at the store
3. Consider the entrance and retention of players, to monetize, to bring the project to the most perfect state.
4. Then repeat several times.
The only way you will be able to quickly experience a game designer and producer in 2-3 years.
After that, decide: do you want to work for a company or to gather your team and make their games.
In any case, you only 21 years old. Even with the development of the only free time you can gain enough experience to 25 years.
Will add other ways through allied professions like:
5. Modders (first make mods for games, then become level designers).
6. Video editors and filmmakers.
8. SMM (come lead the group in social networks, then study game development to the kitchen and another profession).
A lot of ways. But this is all the work. Not just entertainment.