The default password for the RC is 12341234. If that doesn't work you can reset the RC to factory settings in case a custom password had been entered. This is especially common if you are not the original owner. It's also possible you changed it a while ago and forgot.
The password for the aircraft is on the sticker inside the
battery compartment.
You have a third password to activate the drone and link it with your DJI Go app and sync flight data in the cloud. If you forget that one just go to DJI website log on page and click "I Forgot Password" to get email link and reset.