Build an AI powered to-do list app using Flutter, OpenAI API assistant, mongodb and firebase

I need to build a to do mobile app for Android and iOS. The user should be able to add, modify, delete, and see the tasks on the home screen. Each task should include a title, a description, a deadline, materials (PDF, word, pptx, etc.) The OpenAI assistant API will be used to assist the user to complete the tasks and give relevant information. The user will be able to set tasks and the AI will done these tasks in the background and will return the user a notification when the task is completeted or when the deadline is about to expire.