I stuck on the network’s settings with Griddb on my ubuntu

Hostname -i

I got 127.0.1.1

with this command ip -f inet -o addr show eth0 | cut -d' ' -f 7 | cut -d/ -f 1

I got Device "eth0" does not exist

So what do you suggest to fix it? or should I continue to use the ip 127.0.1.1?