Looks like you assigned 192.168.100.2 to the Proxmox host and 192.168.100.2 as the gateway, while your router appears to use 192.168.1.1/24. Try setting the gateway to the adress of your router (192.168.1.1) and chose a free IP address in the same subnet (192.168.1.
xyz) in
/etc/network/interfaces
. There are some examples in
the Proxmox manual.