Connecting a Netgear WiFi extender to a new router can vary slightly depending on the model, but here are three general methods that may help you in most cases:

Method 1: WPS (Wi-Fi Protected Setup) Button

1. Place the Extender: Position the Netgear WiFi extender in the same room as your new router.

2. Power On: Plug in the extender and wait for it to power up. Ensure the Power LED is solid.

3. Press the WPS button on the Router: Press the WPS button on your new router. This initiates the WPS mode.

4. Press the WPS button on the Extender: Within two minutes, press the WPS button on your Netgear extender. The WPS LED on the extender should turn solid, indicating a successful connection.

5. Check Connection: Wait for the extender to establish a connection with the router. The Link Rate LED on the extender should become solid, indicating a successful connection.

Method 2: Web Browser Setup

1. Connect to Extender: Connect your computer or mobile device to the Netgear extender's WiFi network.

2. Open Web Browser: Open a web browser and enter the default web address for Netgear extenders. This is often "http://mywifiext.net/".

3. Login: Enter the username and password for the extender. By default, the username is "admin," and the password is "password."

4. Setup Wizard: Follow the on-screen instructions to run the setup wizard. During this process, you will be prompted to select and connect to your new router's WiFi network.

5. Complete Setup: Once the setup is complete, the extender should be connected to the new router.

Method 3: Ethernet Cable Connection

1. Place the Extender: Position the Netgear WiFi extender in a location where it can receive a strong WiFi signal from the new router.

2. Connect with Ethernet Cable: Use an Ethernet cable to connect your Netgear extender to your computer. This step is temporary and helps in the initial setup.

3. Access the Setup Page: Open a web browser and enter the default web address for Netgear extenders, such as "http://mywifiext.net/."

4. Login: Enter the extender's login credentials (default is often "admin" for both username and password).

5. Follow Setup Instructions: Navigate to the setup page and follow the instructions to connect the extender to your new router. You'll likely need to select the router's WiFi network and enter the WiFi password.

6. Disconnect Ethernet Cable: Once the extender is connected, you can disconnect the Ethernet cable, and your devices should now connect to the extender's WiFi network.

Remember to consult your specific Netgear extender model's user manual for any model-specific instructions or variations in the setup process. 

Source Link: https://www.wirelessextendersetup.org/connect-netgear-extender-to-new-router/