If you mean to display subfolders on the same list view with parent folders, it is not possible with built-in solutions.
It is only supported to group by folders/items on the same level. And I don’t think you can group the subfolders using parent folder name either.
Consider using custom solutions to display all subfolders only in a list view (the parent ...
Not possible with OOB solutions, but technically you can add a tree-view navigation on the page to display the folder structures.
See the references here:
Classic Experience: Sharepoint 2013 : Tree view structure for Document library and setting permissions.
Modern Experience: Tree view navigation using PnP Treeview control in the SharePoint Framework (SPFx) ...