First thing you should know is that the Arduino is not a microcontroller. It is the name of the circuit boards which can be interfaced with arduino IDE (Integrated Development Environment) software. The board uses AVR microcontrollers.
It is very easy to develop projects using arduino, since all the hardware requirements are satisfied in the arduino board itself and the IDE has lot of built in libraries which will make your coding easier tahn anywhere else.
It will take a day or two maximum to finish the code for your project using arduino even if you are a beginner.
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