Install TWRP Recovery on Essential Phone and Root it

Prerequisites

1. This guide is only for the Essential Phone.
2. You must backup all your data because this process may wipe your phone completely.
3. Enable OEM Unlocking and USB Debugging Mode on Essential Phone.
4. You must unlock the bootloader of Essential Phone.
5. Charge your phone up to 50% to make it last through the flashing process.
6. Use original data cable to connect your phone to your PC.
7. Follow this guide carefully. Flashing TWRP and Rooting will void warranty. In case of a mishap, we may not be held responsible. Flash at your own risk.

Required Downloads

1. Download Magisk v14.3 on your computer
2. Download TWRP.img file for Essential Phone.
3. Download modified boot image according to your current build number.
   1. NMJ32F
   2. NMJ20D
4. Download and install Minimal ADB and Fastboot Drivers on your Windows PC.
5. Copy the Magisk.zip, TWRP.img and the modified boot image file to this folder: C:\Program Files (x86)\Minimal ADB and Fastboot.

How to Install TWRP Recovery on Essential Phone and Root it now

1. Make sure that you have unlocked bootloader of your Essential Phone.
2. Connect your phone to your computer now.
3. From the desktop of your computer, launch the Minimal ADB and Fastboot.exe command window.
4. In the command window, enter the following commands one by one.
   1. adb devices
   2. adb reboot bootlader
   3. fastboot devices
   4. fastboot flash boot twrp.img
5. While your phone is in fastboot mode, select boot into recovery mode.
6. Your phone will now boot into TWRP recovery.
7. In TWRP recovery, tap Advanced > ADB Sideload.
8. Now in the ADB Sideload command window inside TWRP recovery on your phone, enter the following commands
   1. adb sideload magisk.zip
      1. This will install magisk on your phone.
   2. adb reboot-bootloader
      1. This will reboot yoru phone in fastboot mode again now.
9. Now it’s time to flash the modified boot image. Make sure that you have copied the correct modified boot image into the Minimal ADB and Fastboot folder.
10. Open the command window on your computer again and enter the following command
    1. fastboot flash boot boot.img
11. Reboot your phone now and you should have it rooted with Magisk running on it. That’s all.

Source