i am not able to ping ip 192.168.2.1 from first router without ip routes why it so why we need ip routes to ping this 192.168.2.1
you need to do routing to ping that ip from 1st router because for 1st router it is different network. Kindly perform below static routing commands in Router 1 and Router3.
Router1# ip route 192.168.2.0 255.255.255.0 192.168.1.2
Router3# ip route 192.168.1.0 255.255.255.0 192.168.2.1
hope this reply clearing your doubt.