Microsoft To Do is a desktop and web-based task list application that is tied into Planner, Outlook, and Teams. You can work through your tasks in My Day or in custom lists, see assigned tasks from Planner, view flagged emails from Outlook. Each list can have an unlimited number of tasks, each of which acn have due dates, reminders, notes, and subtasks.
To Do integrates with Teams, a hub for team collaboration, and Planner, a task list application.
My Day
Use My Day to help focus on daily tasks. You can add new tasks directly to My Day, or add tasks from other lists. To see suggested tasks, select the suggestions from Suggestions at the top of the My Day list.
The My Day smart list resets each night. Any tasks in My Day that aren't completed before the list resets will be saved to your Tasks list and included in your suggestions the following day.

Lists
Tasks
Other Features
Further Reading