Unity Hub is where you create and upload your project. You can create a 2D game or a 3D game. You can choose which unity version you want to have. If you want to make an Ios game then you need to download Ios to your unity version. If you want to make a game for other devices, expect for windows then you need to download them to the unity version.
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In unity Editor there is many windows. There is Console, Animator, Game and more. You can customize you unity editor layout if you want. In unity Editor you can make particles using unity particle system. Most gamedeveloper uses visual studio as a coding software.You need to learn csharp to use the unity engine. If you want to learn unity csharp then you need to check out
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