He, I want a certain group to have access to the admin CP, however I cannot find on where I do that in the core. Could someone help me?
I believe currently you can't set administrative permissions to a group. This does seem like a valid feature so I've opened an issue on github https://github.com/esotalk/esoTalk/issues/387 .
Currently if you want to set a user as an Administrator, go to the users profile, click Control and click Change Permissions. Set the Account Type to administrator and that will give them access to the administration dashboard.
I think to add on to your request, a more robust permissions system could be implemented. We would have to look at how much effort it would take to do an overhaul of the permissions system.