As of first question - yes, you can: just have a look into NetBackup Security and Ecryption guide: http://seer.entsupport.symantec.com/docs/290226.htm
Regarding second question - i doubt that you can do this, as NBU does not support security settings per policy: you can either disable browse for several users or enable it. You cannot show only part of the policies to the group.

Have you investigated "User" directed backups? They are initiated from the NetBackup client. The user must have read privileges to the folders/files that is to be backed up. The user cannot backup another user's files unless the user has read permissions.

stumpr what you are trying to say????
my question was different.

Do i assign/delegate particular policies to particular users and the users are not able to chage the other users policies

User directed backups are different. You can create a schedule within the policy for user directed backups. User backups are FULL backups. The user selects the files to be backed up andf can only run the backup during the window defined in the schedule. The user can only backup files that they have read permission. I don't know if user directed backups will meet your needs but I wanted to offer it as a possible solution for users that want to start their own backups.

This may or may not be an option to you specifically but it could be a thumbs up to another forum reader who is looking for more options in their Netbackup environment.

Here is a screenshot of the User Backup policy (in red).  In this instance, any user under this policy can manually run their own backup between the hours of 8AM and 5PM M-F that will have a 2 week retention.