Is OAuth2 TokenScope similar to Django Permissions?
Actually there is a difference between Django permissions and OAuth token scope, Django permissions use for define access level to your endpoint addresses like when you want just authenticated user see some data but OAuth token scope is for time you want to have third-party login and you define when somebody login what access he/she has, like when you authenticate from Gmail in scope Gmail, for example, says read and you just have read access when you login .
and I didn't get you concern number 2
I'm building a dedicated OAuth2 as a service for my application, where users will be both authenticating and authorizing themselves. 
I've the following concerns
1) Is OAuth2 TokenScope similar to Django Permissions?
2) If I want to make role-level hierarchy application, how do I go about building one with OAuth2?