It is generally not recommended to grant any bot ircop privileges. However, in order to grant your eggdrop such privileges, you'll have to make it send the OPER command with proper parameters. To do this, use any of the puthelp, putserv, or putquick commands.
To send this on join, have a look at the server-init evnt binding within the default config-file to see how you can execute commands after your eggdrop connects to a server.