If NHRL is what you want to do then checking out an r/c airplane club and asking questions may be a way to get started. That's going to give you an idea on how transmitters, receivers with multiple channels and servos/speed controllers work.

Once you understand how transmitters/receivers work and what servos and speed controllers do then you can construct a chassis. The speed controllers would drive the motors moving the robot around and then a servo could open the valve on a flame thrower or something...

They key is understanding the radio control tech first.