how to get digital i/p from router Xbee s2 and give digital o/p in same router via arduino using Xbee's I/O's?

XBee & XBee Gateway XCTU
,
2

For an Input, try setting the desired line as Digital In and then issuing the IS command. For output, you will need to use the remote AT command functions via the API interface to change the output values from High to low.