Internet Access and UART Access in "Olimex A20-OLinuXino-LIME2"

[Tejas]

I'm unable to access internet through USB tethering, on network manager connection reflects as "device not managed" on "Olimex A20-OLinuXino-LIME2" along with latest a20 image "   A20-OLinuXino-focal-base-20210707-172415.img.7z". Also, my final aim is to connect SIMCOM broadband via USB to olimex so need support for that also.

I need to understand how to access UARTs of Olimex A20-OLinuXino-LIME2 (any 3) also.

Thanks in advance.