Vcc to 12v external power +
and
GND to external power -
Then
PWM is connect to D11 pin of arduinoIs this correct?
Yes. Plus Arduino ground to external power ground.
Im sorry i can't understand about the ttl and pwm
Think of it like this. They are not two things but PWM is a way of using a TTL signal.
TTL is a signal an Arduino output, PWM is something you do to that signal.
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