How to install ubuntu img.gz image???

hello everyone

ubuntu official system provide img.gz image,however, the installation method is not provided。
Does senior know how to install it?

An img (image) file is normally a disk image, so you can just dd it to a disk after uncompressing it with zcat (for a pipe) or gunzip (for a file). Or in other words, you can use the same command you used for an OpenEmbedded wic.xz file, except you use zcat instead of xzcat.

Download Ubuntu for RISC-V Platforms | Ubuntu links to RISC-V - Ubuntu Wiki. Which information are you missing in the wiki?

Try the Installing Ubuntu instructions in this blog post: https://arch.cs.ucdavis.edu/blog/2022-09-15-perf-hifive