Beginner in using XBee S2C Transmission in API mode

Can you give me an example code in transmitting data in API mode? I try several codes in the internet but none is working. The receiver is the Coordinator (AP=1) and is connected in the laptop with XCTU. I am sure that my configuration of 2 Xbee is correct. 1 Coordinator (AP=1) and 1 Router (AP=1).

Do you need Arduino code or what?