Is it possible to have admin account with Oauth please? How? I cannot figure it out 
Hello & good day!
Someone else can chime in of course, but I’m not quite understanding the ask. Is it that you want certain accounts you use to login with OAuth to be admin accounts?
I’m assuming you’ve double checked the documentation on how to set up?
But my guess would be that you first login with your desired OAuth account that you want to be an admin, log out, login with your local admin, make your OAuth account an administrator, logout of local admin, re-login now as your OAuth-based administrator, then remove the local admin if you so desire.
We can start there and drill down to your needs if I am misunderstanding