I've never done uboot/tftp installation before, I tried to read the instructions for the device on this page:
https://openwrt.org/docs/guide-user/installation/generic.flashing, specifically Method 2 ( via Bootloader and an Ethernet port).
The 8 steps outlined in the page is not very clear to me.
I am using linux. I can install tftp client or server on my linux.
I don't know if the router has tftp server or client.
Please help. Thanks