In the United States, Google Pixel phones come in carrier-locked versions or factory-unlocked versions. Whichever version you get, Google and most of the carriers allow you to enable OEM unlocking so that you can unlock the device’s bootloader to install a custom Android operating systems. However, this is not the case with Verizon.

The Verizon Pixels prohibit their users from unlocking bootloader, thus, you cannot install any custom Android OS on it.

To check if your device allows you to unlock the bootloader, you can try enabling OEM unlocking:

• Step 1. Enable Developer Options
  Settings → About Phone → tap Build number 7 times
• Step 2. Enable OEM Unlocking
  Settings → System → Advanced → Developer Options → OEM unlocking

The last step may fail if there is no internet connection. In that case, you need to connect to a Wi-Fi network, remove the SIM card, and then try again. Once OEM unlocking is turned on, always remember to turn it back off if you don’t need it.

Please note: If you can enable “OEM unlocking” on your device, it means this phone allows bootloader unlocking and you can install CalyxOS. If “OEM unlocking” is greyed out, you may have the Verizon version. Please keep in mind that unlocking bootloader is different from unlocking a carrier-locked phone.