Two types of different entries with firebase

Oops, I'm having a hard time installing a registry system with two different users, I'd like to be registering a user of type adm and a common user, however I'm displaying the data in a fragment with firebase and for that I need to pass a child with the parameter from where it will fetch the data ... But with the adm it error, error in which I should pass the child with the adm node to solve ... How to do to change the types of users who would log in and pass these parameters to that child based on the user's option, or else how to do for the firebase to pull data from two different childs in the same reference ???