Have you already taken the first step, namely unlocking the bootloader?
The most time-consuming part of the installation process on a Xiaomi Pad 6 (codenamed pipa) is unlocking the bootloader.
If you still have the Xiaomi Pad 6 Global firmware based on Android 13 installed, unlocking the bootloader will take 168 hours (7 days) from the time you apply to Xiaomi.
If you have already installed the Xiaomi Pad 6 firmware HyperOS based on Android 14, unlocking the bootloader will take at least 720 hours (30 days), more likely more, from the time you apply to Xiaomi. Especially here it becomes clear how Xiaomi harasses its users. It is not enough to apply to unlock the bootloader as before, no, the user must also install and activate the Xiaomi community app. See for example here
If you have the China version, unlocking the bootloader is only possible with a Xiaomi China account since the end of October 2024 - if at all. Nothing works with a Xiaomi Global account. Xiaomi is increasingly moving towards preventing the bootloader from being unlocked.