you can probably just follow https://openwrt.org/inbox/toh/xiaomi/ax3000t#change_to_openwrt_u-boot, starting at 2, since you've booted the initramfs via boot loader.
you can probably just follow https://openwrt.org/inbox/toh/xiaomi/ax3000t#change_to_openwrt_u-boot, starting at 2, since you've booted the initramfs via boot loader.