Hello Priyanka,
I suppose you have an entity with a boolean attribute ‘completed’:
All items with completed = true will be at the bottom of the list. Vice versa you could select descending to show them at the top.
Please select my answer as accepted if this helped you. Thank You.
If you are using a ListView or DataGrid, set the sort order so uncompleted items are at the top of the list. Then when you complete an item, it will move to the bottom of the list.