I recently installed openWrt on my ubiquiti unifi AP lite, but It doesn't give me access to internet. It has only one ethernet port, so its connected to another router. My surprise is that i have enabled one ssid, and it allows internet connection, but when I'm inside the AP via ssh, i cannot make curl, ping, etc, it doesn't allow me to connect into internet.

The /etc/config/network is like this:

config interface 'loopback'
        option ifname 'lo'
        option proto 'static'
        option ipaddr '127.0.0.1'
        option netmask '255.0.0.0'

config globals 'globals'
        option ula_prefix 'fdcf:6603:b544::/48'

config interface 'lan'
        option type 'bridge'
        option ifname 'eth0'
        option proto 'static'
        option ipaddr '192.168.1.20'
        option netmask '255.255.255.0'
        option ip6assign '60'

What's the problem? Why can't I connect to internet? Thank you

You need to tell it the address of the main router as gateway and dns in the lan section.  Then it knows to go to the Internet via that other router.

    option gateway '192.168.1.1'
    option dns '192.168.1.1'

Thank you very muchm my problem has been solved!!!!