A general help *Completely new to Arduino*

ishabana:
The project basically should have 3 standalone Arduino boards, each should read a number from an online API, then send it to a center board (Arduino as well but connected to a machine) where I want to do some math with the received numbers, then send to a machine (PC) where I am taking it from there and use these data in other platforms I am familiar with (ex. Quartz composer and processing).

Why is a Arduino of any kind needed? ? ?

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