lora E32-900t20d + TTN gateway

Hello I have an arduino mini 168 5.5v, a lora E32900TD module and an indoor gateway from the things network TBMH-100 model, i managed to configure the arduino with my module and added the gateway to the TTN. However, I tried to used the ABP method key that I found online for an sx1276 module, it turned out it was not the same for UART interface. I cannot find any useful guidance. How to make them communicate please this is a student project. appreciate your kind support.