Android app online tutorial

We are a startup and we are building an online tutorial. We want an android app as a platform for it. It will be similar to that of Byjus'. We are a startup and we are building an online tutorial. We want an android app as a platform for it. It will be similar to that of Byjus'. The First Page will be a LOG IN screen. Log In should be done only by Google account. There will also be a link to try a free demo. There will also be some other information which can be changed as and when required. The Try a Demo will link to a page which will collect some personal information about the user and store in a Database. The Second Page will show subject wise Lectures, Study material, Quiz and Comments. The comments will be visible to everyone who visits the page. Admin should be able to delete it. The Lecture option will show the video in a player. Plz note that the video player should be in app and not Youtube or other embedded. Some time-based questions need to be displayed to keep the audience engaged. The video should not be downloadable. The Study Material section will have text, photos and links The Quiz section will have multiple choice questions which will be time-based. Once the user completes the test or time ends, the answers need to be shown and marks need to be calculated. There will also be negative marking for wrong answers. There will also be a menu option. If the user slides it, he can access lectures subject wise. He will also see the Quiz he has not attempted. The My Score will be the total marks of all the quiz he has been allotted. The My Library will be like a Google Drive where PDF can be downloaded from. The Feedback section will have a basic form where feedback can be submitted. Since this will be a live app, we will require an Admin panel to manage everything. The Admin Panel will have a Sign In Section. Once Signed in, the admin will be able to Add User, his email Id and other info required. He will also be able to Add Courses, Subjects, Lectures, Study Material, Quiz and documents in My Library. Plz look at Photos Admin 1 and Admin 2 I have uploaded below.