How to setup static ip connection between router and linux?

Question

linux

The circuit I want is:
The computer is connected to the internet via wifi (router 1).
Another router (router2) is connected to the computer through the wan port, and gives access to the Internet to all devices connected to it.
What I have already done:
On the router (router2) I manually configured wan with the following parameters:
ip: 192.168.100.2/24
Gateway; 192.168.100.1
Enabled DHCP on lan:
Network:192.168.0.0/24 Registered
on the computer:
sudo ifconfig enp3 192.168.100.1 netmask 255.255.255.0
What is my problem:
Router2 does not ping from the computer :
ping 192.168.100.2
from the phone connected to router2 to check)
PS
the route -n command on the computer gave the following result:
Destination gateway genmask
169.254.0.0 0.0.0.0 /16
192.168.100.0 0.0.0.0 /24
I have no idea where the first entry came from, it appeared when executing the ifconfig enp3 192 ... command. ..... (see above)
What am I doing wrong?

Answer 1

I would look at ifconfig and /etc/network/interfaces

Answer 2

The firewall on router2 blocks ICMP packets.
You can read about 169.254.0.0/16 here: https://en.wikipedia.org/wiki/Link-local_address