1. do i need to perform by babystep upgrade (current version is adventerprisek9.02.04.01.122-33) or i can upgrade straight to that version?
Yes, you can go direct.
2. do i need to get license first before upgrade. Hence ver12.2 does not have the license command?
No you don't.
To upgrade both the OS and the ROMmon, copy the OS into the bootflash. Change the boot variable if needed.
DO NOT BOOT THE ROUTER YET.
Upgrade the ROMmon using the command "upgrade rom file flash:// all".
This way, the router boots up ONCE.