This method of unlock bootloader will work on all Xiaomi/Mi Devices. I’m using POCO F1 in this video. You can unlock bootloader of your Redmi/POCO/Xiaomi mobile.
How to Install Custom Recovery and Root for All Xiaomi Mobile Devices(Easiest Method) https://youtu.be/bPAaR6JizT0
Download Mi Unlock Tool Software from this linkhttps://en.miui.com/unlock/download_en.html