To segregate the admin to specific board, follow the steps below:
Click New under Board/Committee
Create a new Board/committee and select Next
Choose the individuals to whom you wish to grant access to the Board. Please note that when you select an individual and do not select "change to owner", they can add/delete/update/publish binders.
You can alternatively select "change to owner". Owner means the admin can delete board, modify the board's settings, can manage adding or removing other admins to the board. Please note that they can also perform the functionalities mentioned in the Step 3.
Once you have provided the access, please click Save and Close
⚠️Good to know: The board permissions/ownership can be setup:
When creating a new board (as you've outlined)
When modifying an existing board
When creating an admin
When modifying an existing admin