1. Click the Network icon on the lower right corner of your screen.
   
2. Then click Network Settings.
3. In the Settings window click Manage Wi-Fi Networks.
4. Click on the wifi network you want to remove.
5. Then click the Forget button.

Apple macOS

1. Click the wireless icon in the upper right corner and click Open Network Preferences... at the bottom of that menu
2. Make sure Wi-Fi is selected on the left and click the Advanced... button
3. Under Preferred Networks, click the name of the network you want to remove.
4. Click the minus (-) button below the box to remove the network then click the OK button.
5. Click Okay and Apply in the previous Network window to save the changes. You may also need to turn the Wi-Fi off and back on again to see the change.
   
   

iPhone or iPad

1. Go to Settings, then tap on Wi-Fi.
   
2. Tap the blue "i" at the end of the line after the name of the wifi network you want to remove.
3. Choose Forget this Network.

Android

1. Enter your device's Settings via the app or gear icon.
2. Tap on Connections.
3. Tap on Wi-Fi.
4. Touch and hold the name of the wifi network you want to remove and then tap Forget network from the menu that appears.