1- Install TWRP using XDA guide. (unlock-bootloader + flash TWRP.img file + flash Disable_Dm-Verity_ForceEncrypt_11.02.2020.zip file)
2- Reboot your device into recovery.
3- Wipe System , Cache , Data , Dalvik-ART-Cache (Reset factory)
4- Flash the vndklite GSI .img file to System partition.