If you wish to search your Extender’s Wi-Fi network password, you can go through the instructions below -

1 Connect your computer or a wireless client to your Wi-Fi Range Extender via Ethernet or wireless connection.
2 Open an Internet browser on your device.
3 Enter the web address www.mywifiext.net
4 You will be directed to the Login page where you can log in using your Username and Password.
5 Next go to Settings, you will find the Wireless settings there. Click to go into the wireless settings
6 In the Wireless settings, find the General settings, click on it and look for Wifi Password.
7 When you find the Wifi Password setting, click on it and see if it shows ‘Same as existing network password’. If it does, then it is using the same Wifi password as your mainWifi router.
7 If it doesn’t show that but instead shows ‘Use a different password’ there, then it will show the type of password under the Security Type and the Network Key settings.

https://www.my-wifiext.net