I wrote a little java sсrіpt (ToDo-list). The following functions need to be add

I wrote a little java sсrіpt (ToDo-list). The following functions need to be added:
1.
Sort by completed & uncompleted tasks
2.
-Filter by completed & uncompleted tasks
3.
-When a task is newly created set a due date
4.
-Sort by due date
5.
-Filter by due date
6.
-Delete all completed tasks with the X button (at the bottom)
7.
-Save tasks
Review my litte sсrіpt and optimize it including comments.