“I am trying to access Capella from my application but its not happening may be I am not able to properly whitelist the IP. Actually I am behind a firewall and not sure about the outgoing IP is there any way to whitelist all or how to know which IP range to whitelist?”
If you work for a company you would need to contact your IT department to find out the range. If you are doing this from home - you can just type into a google search:
find my ip address
HIt search and it will tell you the IP address. Your ISP can tell you how often your IP address changes - and you will have to add/delete your IP address each time your IP changes. If this is a home connection for security reasons you should always only whitelist your IP which means you need to use a /32 or 255.255.255.255 for your subnet mask which means it will only use that single IP address.