adb – How to install recovery image with fastboot? (Asus zenfone go 5.5 zb551kl)

I have an old phone “Asus Zenfone go TV zb551kl” and I am trying to fix it so I can give it to my nephew. It had a problem where the only thing that it can load is the “fastboot”. And, it says “Invalid boot image!!” whenever I boot recovery or normal boot. I just want to install the stock recovery image so I can re-install the stock ROM.

I’m just wondering if someone can help me with my problem.