How to access mobile SIM card for flexiload and bkash?

Question

I have a C# project to access SIM card from modem device 

Actually I have a easy-load SIM card and I want to load to different mobile SIM card through

this desktop based software and access flexiload menu with bkash, Ucash etc using modem device.

I don't know how to access this devices and SIM access command.

Anyone please help me I need urgent help.