To be honest, I’m not exactly sure if I understand you correctly. Also, you didn’t mention the operating system you use.
But my shot in the blue would be, that you are on Windows, where the basic icon for the file manager would be called something like “Computer” or “My Computer” and that in your file manager you have switched from icon view to list or details view. Which is what you need to explore, to get back to the icons view. Shouldn’t be a big deal 😉
The according setting is usually somewhere in a top panel on the right hand side. Another option would be, to look out for a menu item “View” and find according settings there. You could also try a right mouse click inside the window and see, if you get some view options there. All inside the particular file manager window, where you images are listed.
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