Why my scooter is not working?

Something is lost in the translation. A scooter is relatively simple electrically. A battery, motor, on/off switch, speed control and associated wires and connectors. The electronics for the speed control is likely a sealed PWM module, so no need to get into that.

You must start at the battery with a DMV. and trace the power to the switch, then to the Speed control and to the motor.

HOWEVER, you can learn a lot by manipulating the controls to see what happens and what does not. Post a detailed description of that and someone may be able to point you to the problem.