Genuine Arduino microcontrollers are great brains for your first robot. We strongly recommend starting out with an Arduino because they are simple to use yet powerful enough for many small robot projects. There is a large community on the Internet with lots of useful examples to assist your endeavors and inspire your creations.
Learn Arduino electronics with the Official Arduino Starter Kit. Includes an Arduino Uno, breadboard, servo, motor, LCD, RGB LED, light and temperature sensors, electronic components and more. It comes complete with a detailed Arduino Projects Book with more than a dozen fun projects.