Is it possible to change a view from a user view to a node view?
There is no automatic way to convert a user view to a node view or vice versa.

Although you probably could get away with manually combining the fields from the export of your user view with a plain export of a new node view, it would be faster and a lot less problematic to just open the old view and your new view side by side in two browser windows and recreate everything.

Unfortunately a lot of Drupal site building is just checking checkboxes...