The short answer is: The long answer requires understanding hardware restrictions, OEM policies, and advanced workarounds.
But what if you don’t have a computer? What if you are on the go, with only your phone and an unbreakable will to mod? This is where enters the conversation. unlock bootloader via termux
For Xiaomi (before 2023), you could request unlock permission via Mi Unlock Tool (Windows only). No Termux. The short answer is: The long answer requires