Adb

Download the platform tools here

Useful commands

  adb devices

  adb shell

  adb reboot download
  adb reboot-bootloader
  adb reboot recovery

Errors

error: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.

   Try Revoke USB DEBUGGING Authorization.
   Enable USB debugging again.

Check the screen and make sure you allow the PC for always.