Hi krishnaprasad,
Sure i can help you.
Here's what you are doing. You are logging into the host directly and creating a local user. And you are trying to add that user to vcenter permissions. The "local" user that you created on the host is local to your host and will not appear in vCenter. It can only be assigned when you log into the host directly using vSphere client.
Do this.
Go to your vCenter roles, Create a role with just CIM Interactions.
I hope you have a domain mapped to your vCenter. So create user on the AD as CIM-user.
Now click on vCenter and go to permissions, Click Add permission. Import this user CIM-User with the CIM Interactions role and click ok.
Now the user will be able to do the CIM tasks on each host.