Important First do full backup of your device

Not Working :

• WiFi does not work

Device

• Flash Ginkgo Vendor if you are using Redmi Note 8
• Flash Willow Vendor if you are using Redmi Note 8T

Step 0 : FLash Android 9.0

• Flash stock android 9 vendor (for example i used V11.0.10.0.PCOMIXM)

Download your preferred rom from here

You have many options here for example you can Flash via:

• Xiaomi Flash Tool
• Or Fastboot
   

Fastboot instructions (Linux user) :

Enter into fastboot for me (power + volume down) or

adb reboot bootloader
fastboot devices

flashing script

tar -xzvf willow_android9_path.tgz && cd willow_android9_path
sudo chmod +x flash_all.sh
./flash_all.sh #flash android 9 vendor

it take times when it's done reboot your device and configure android basics then activate activate again developer options
(1. oem/unlocking , 2.usb debugging, 3.usb security debugging )

Step 1 : Flashing twrp
 
  Download twrp app for example i used this one
  Download vbmeta for example i used this one

  Enter fastboot and then flash twpr

fastboot flash vbmeta vbmeta.img
fastboot erase recovery
fastboot flash recovery twrtp*.img
fastboot reboot recovery

or you can enter twrp mode via (Power + VolumeUp )

Step 2: How to Flash
Enter into twrp mode (Power + VolumeUp ) and wipe your data

Download these ubport files on your pc

• halium-ramdisk: link

• kernel: link

• GSI V10: link

• ginkgo patches: link

  go to advanced -> adb sideload and load these downloaded files and from your pc load there file

adb sideload halium-ramdisk.zip
adb sideload ginkgo_Kernel_4.14-20201015-0455.zip
adb sideload ubports_GSI_installer_v10.zip
adb sideload ginkgo-postinstaller.zip

or if you have sd card copy these 4 file your sd card from pc and then go twpr -> install -> select storage -> micro sd storage -> and install these zips follow "sideload" sequence