Help with library API

Could help me, I'm using the API library (GitHub - andrewrapp/xbee-arduino: Arduino library for communicating with XBee radios in API mode) and am finding it difficult to configure them in AT mode. I'm using and enjoying the examples, but are not working, nothing happens. Place the modules in API = 2. Could someone help me with some example or explain? do not quite understand its operation. Also wanted to know how to send the API frames, I'm sure I'm riding the frames correctly.
I'm using XBee series 2 and trying to first make a point to point communication to configure them

Thank you for those who can help me

Can someone tell me how to configure a node using api library?