How to assign manage teams as admin

We have desided that only admins can make teams and so making office 365 groups.
Problem now is how can i make a team based on a o365 sexurity group or not make groups for other departments without being a member of the group itself?
Also when we give certain users rights to make groups / teams for there department is how to do that without beiing the owner member of the group or team site? When i go to the admin team centre i can create teams but the 0365 groups are not available for selection to base the team group on. I have read that you must be the owner to create a team based on 0365 groups but then the admin is always a member of all groups?