Learning flutter requires you to be familiar with object-oriented code and basic programming concepts such as variables, loops and conditionals, but you don't need previous experience with Dart or Mobile Programming.
If you are not aware of which programming language Flutter uses in background, its Dart language. It's been developed by google itself.
From my experience, setting up the flutter environment requires a minimal effort as the instructions are clearly provided by Google in their Flutter Site. Once you are done with the Setup and create a first app (which doesn't require any modifications to the code) you are ready to run it and see the fun.
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