C++ Autonomous Code Inaccurate Using VEX Drivetrain Object

But I can’t start everything at 0 or the motors won’t turn at all. This forum post recommends that I start kP at 1 (How to set KP value of a pid program - #3 by ZachDaChampion) and then increment until it overshoots or starts oscillating. Is it fine to start kD at 0 until I have tuned kP, and then increment kD until the error is almost 0.

Also any tips on how to convert robot movement or turning to motor degree rotations. Right now, this PID control takes in motor degrees, but I don’t know how many degrees the motors need to turn to drive say 24" or turn 45 degrees.