First you need to unlock the bootloader. Since you have a Chinese device, you need to find a paid online service (for example nculock) to unlock the botloader.
Once you have the boozloader unlocked, follow these instructions:
Installation instructions xiaomi.eu Install drivers, ADB and fastboot install Xiaomi drivers 1- First, update the ROM to the latest using the updater. 2-Unlock the bootloader https://xiaomi.eu/community/threads/unlock_hyperos_-global-devices.71752/post-720918 3 -Download the ROM : Stable...
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