I am glad you youngsters can get started with safe devices, I started building projects with valves ( vacuum tubes ) with a home made high current 300 volt DC power supply - absolutely lethal.. I guess I was lucky.
I'm learning programming now so I will have something to share with my Great Grandson in 13 years time 
( he is due Sunday )
You will find so much help and experience from the people on this forum ( and just ignore the occasional sarcastic replies from those that don't realise the Arduino and this forum was made for beginners ! )
Good luck, and with your experience in C, I dont think you will be just blinking LEDs for long ....