Connect your USB cable and launch an ADB terminal.Reboot your Pixel 3 to the Bootloader as we showed you in the unlocking guide above.Important: Set a security PIN before installing TWRP (Settings > Security & location > Screen lock > PIN). Root Pixel 3 with Magisk, Pass SafetyNet with TWRP When the process is done, you type into ADB terminal: fastboot reboot.Then just follow the on-screen instructions to unlock your bootloader, and remember, all of your user-data will be reset!.When your Pixel 3 device boots into Bootloader Mode, you can then type into ADB terminal: fastboot flashing unlock.If your device is successfully recognized by ADB, type the following command into ADB terminal: adb reboot bootloader.

This should display your device’s serial number in the output prompt – if it says your device is not recognized, device offline, or displays no device at all, you may need to try reconnecting the USB, or troubleshooting your USB drivers (also accept the ADB pairing dialogue on your Pixel 3 screen).

To make sure your Pixel 3 is recognized by ADB, type in the terminal: adb devices.

Launch an ADB terminal ( hold Shift + right click in your main ADB folder and choose ‘Open a Command Window here’).

Connect the phone to your computer via USB cable.

Now go into Settings > Developer Options > enable both OEM Unlock and USB Debugging.

Enable Developer Mode by going into Settings > System > About Phone > tap Build Number ( 7 times) until you see Developer Mode has been activated.

It is highly recommended to backup your data before proceeding, as unlocking the bootloader will erase all of your user data from your Pixel 3 device!

How to install adb on windows