In reply to Ashish Jha.

Hello Ashish,

There are a number of places you can go to start learning about IOS/XE:

– https://blogs.cisco.com/
– https://supportforums.cisco.com/
– http://www.ciscopress.com/
– https://www.ciscolive.com/global/on-demand-library/
– YouTube – if you search for Cisco IOS a number of results will return

Best of luck to you in your journey.
Regards,
Zach Spicer
Cisco PSIRT Project Manager