Most users prefer the community-maintained platform tools for Termux. pkg install android-tools Use code with caution.
Once in fastboot mode, verify the connection: fastboot devices Use code with caution. If your serial number appears, run the unlock command: fastboot flashing unlock Use code with caution. unlock bootloader using termux better
Standard Termux doesn't come with ADB (Android Debug Bridge) or Fastboot pre-installed. You need to install a repository that hosts these binaries. pkg update && pkg upgrade Use code with caution. unlock bootloader using termux better
Ensure both devices have at least 60% battery. If the host device dies mid-flash, you risk "bricking" the target device. unlock bootloader using termux better
(Note: Older devices might use fastboot oem unlock instead.)
To unlock a bootloader using Termux, you technically need two devices: The phone running Termux.