Add some features to Android App and the Web Admin panel and fix existing bugs

I have an android News app and i want the following features added to it 1. User Management System added to both the web admin and the android app. The categories of users will be ADMIN | EDITOR | TEACHERS | STUDENTS. Currently, only admin is the user in the backend. ADMIN -- Can do all activities in the back end (including adding and deleting users, news, comments, settings etc.) EDITOR -- Can edit and delete coments, upgrade other users to TEACHER, but, EDITORS should not be able to post News but can modify other News Posted by TEACHERs. TEACHERS -- Can post News, delete and update News; But they can not edit or delete News that other account Posted. Each TEACHER account can only work with the News Posted under his username. 2. There is bug that need to be fixed with the login and sign up page within the app. The login/sign up page needs to storage and pull data from the admin back end. Currently only the login/sign up template is what is inside the app. 3. Every post inside the News App should have a comment and reply system where users can comment and others can reply to comment and follow. Please this should be secure so that the comment form does not allow the app to be vulnerable. 4. Bugs related to posting News or Adding News categories in the Backend should be fixed. 5. Only YouTube video can play inside the app, i want other type of video files to also be able to play. You can add another Video Player and specify the option in the back end when teacher want to upload that they can choose YouTube Video OR Other Videos