Installing luci gui with a pppoe connection (No internet access)

Installing and Using OpenWrt Network and Wireless Configuration
1

How can i install luci gui with a pppoe connection? i do not have internet access because i can not access openwrt to configure it....

Can i install it offline? how?

2

https://wiki.openwrt.org/doc/howto/luci.essentials#minimalistic_offline_installation

?