I think the best place to learn about computers is on the internet. If you own any popular games already, I think a good place to start design would be with modding a popular game. If you are able to create a popular mod for a popular game, this can work as a resume to be a paid game designer, or to make a full game and sell it solo or as a team as a designer. If you want to be a pure designer, it might be possible to find a forum specific to that games modding process and meet people there who enjoy the other parts of mod making and game making. Note that modding has all the same parts, in that you can edit any and all parts of the game, but when you're new it's best to start small and work with how the game already is, then explore the different areas of modeling, level design, ai, scripts, and code, in around that order. Note that specialization may be done, or not, or some mix, along with communication. A good way to learn is to start with tutorials and reading about it online, probably using google to find information about modding your favorite game. Make a few experimental mods that aren't really meant to be playable or fun, but are more of a learning to use the tools experience, then once you've learnt about a few fun looking tools design a new game type that will hopefully be fun, make it, and publish it online to build a rep and have fun, learn skills, and maybe get a job as a pro modeler, leveler, or whatever with your fun mod as your resume.

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