Configure

$ doas rcctl enable dhcpd
$ doas rcctl set dhcpd flags em1
/etc/dhcpd.conf
subnet 38.87.162.0 netmask 255.255.255.0 {
        option routers 38.87.162.1;
        option domain-name-servers 38.87.162.1;
        range 38.87.162.2 38.87.162.254;
        host username {
                fixed-address 38.87.162.2;
                hardware ethernet aa:bb:cc:dd:ee:ff;
        }
}
$ doas rcctl restart dhcpd