You can edit the columns or the view for a custom view that you have already saved by following the below steps:
1. Click on the specific View that you want to update by clicking on the 3 vertical dots on the right and select Update Current View.
2. You can add column headers or even reorder its arrangement in the view grid.
3. You can also drag a filter to the teal horizontal line to further specify your view.
4. You can also update the view name, make the view public or private or default.
5. Once you have made your updates, click on Update Filter.