Edit a public or system view in app designer
You can change the way a public or system view is displayed by adding, configuring, or removing columns.
* In the Views list for a table, select the Show list of references down arrow Drop Down. Edit View.
* Next to the view you want to edit, select Open the View Designer Open view Designer.
The view opens in the view designer.
When you edit a public or system view, you must save and publish your changes before they will be visible in the application.
Reference:
https://docs.microsoft.com/en-us/powerapps/maker/model-driven-apps/create-edit-views-app-designer