File Explorer Just Got More Difficult

I tend to drop files into a folder, then later move them to a subfolder. In Win 3.x to Win 7, that was easy: if you were in a folder, you could click the little arrow to see the subfolders, and drag files into them.

In Win 10, that was originally still doable, but harder. The right pane would show the folder contents, but the left pane would show "Desktop" or something like that. So to see the subfolders of the folder, you had to click on "This PC," then click on the drive where the folder was, thenclick the little arrow.

Is there a way to get back to a format where I can have a folder open in the right pane and see its subfolders in the left pane without all the extra clicking?

Thanks! Ctrl-Shift-E worked...just hope I remember it. Could not use the first two solutions because I see no ribbon in my File Explorer.