Why did the server lose its connection to the Internet?

Question

ubuntu

I put ubuntu-server on a neighboring computer, connected it to the main one (win 10 is on the main one), on the main one I also allowed Internet access from the wifi network to the ethernet network. Everything worked, the Internet "spread". The next day I turn on the computers and notice that there is no Internet on the server. I started trying to change ip, reconnect the network, reboot computers, reset the network, no results.
What is interesting - on the server, ping does not work not only on sites, but even on a neighboring PC, namely:
ping 192.168.0.1 -v

ping: socket: Permission denied, attempting raw socket...

Myself (192.168.0.2) and localhost server pings fine. I have never encountered such a situation and cannot find a solution in the forums. Yes, while the main computer normally pings the server, as it connects via ssh ... I think that the key to the puzzle is in the ping error.
Actually, why does the ping error occur?

Answer 1

as quoted, there are interesting messages in Google,
start with routing