OpenWRT: first time login and configure pppoe

I flashed my router  via a firmware without luci(web interface).

I need to configure wan and wifi

ssh root@192.168.1.1

passwd

vi /etc/config/network

find

config interface ‘wan’
option ifname ‘eth0’
option proto ‘dhcp’

change to

config interface ‘wan’
option ifname ‘eth1’
option proto ‘pppoe’
option username ‘your username’
option password ‘your password’

save

/etc/init.d/network restart

and I can access internet.