timers and interupts

If I wanted to run brushless motor on an ESC for a preset amount of time after it receives an input to turn on I would want to add an interupt, correct?

No

what would I need then?

Scan your switch every ~50ms and look for a change in state to LOW or HIGH.

Here are typical switch connections.

2017-08-05_20-33-24.jpg

See the change in state switch example.
https://www.arduino.cc/en/Tutorial/StateChangeDetection

just use the servo library, and when the Arduino receives the command to turn on, have it run a version of this function

void motor(){

Serial.println("Sending maximum throttle");
                      motA.writeMicroseconds(MAX_PULSE_LENGTH);

delay (1000);


Serial.println("Sending minimum throttle");
                      motA.writeMicroseconds(LOW_PULSE_LENGTH);

}

Thanks