Initial brake

Urgent

Could you tell me what is the meaning of initial brake?  Initial brake is not equal to max brake right?

Initial brake would be the brake force applied at the very start of your braking.
usually have an option to make the initial brake force same as drag brake force, which then allows for a smooth transition between off throttle(neutral) and braking.
Max Brake is brake force applied when the throttle stick is in full brake position.

OK.  Thanks.

But my friend said it is not necessary to make the initial brake same as drag brake, because drag brake is very small percentage, sometime user set it to “no drag” or 0%. The user won’t feel the difference even drag brake and initial brake is different setting.  Is it correct?

yes correct.
it is not necessary to set drag brake same as initial brake... just depend on your driving style/preference.
if you set your drag brake to 0% and initial brake to 100%, then i think you will feel the difference as well as break your spur gear.
For me i dont use brake when driving (only to stop car or avoid crashing)
my setting is drag brake 0% and initial brake 20%