Hi, The base kernel dont have usbserial , fusion, ppp and other modules wich need to connect the internet with LTE/3G modem. Im configured the usb_modeswitch, but it cant load the option module with the base kernel. Im compiled an own kernel with the necessary modules(compiled just only the modules)...
In the make menuconfig-> device drivers -> usb support -> "USB modem support"
and under the USB serial converter support most of them as modules.