help me plzzz

i m just asking how can i make to motor turn

That's one thing.

for like 3 sec

That's another.

Before you get into trying to control your motor over the internet, you should make sure you can control it with a dirt simple sketch. There are several examples provided with the IDE that control servo motors. Give one of them a spin.

Then, there is the blink without delay example that lets you start something happening, and stop it later. Read, understand, and EMBRACE that example to turn your motor off 3 seconds after it was turned on.