I am in search of the information that will help me access my old 3.5inch on an external usb adapter, with my laptop. Or if someone can tell me how to do that right here that would be better. Thanks
In theory, it should just work. That is, if the 3.5 inch disk is connected properly, when you plug in the USB connecting the external disk to your computer, Ubuntu should just recognize it. Then, it should either appear on the sidebar, or when you open a folder, you should see it under 'devices.'
If that isn't happening, then I would guess that it's a hardware issue and not a problem with Ubuntu. To verify this, you could try plugging it into a different computer and see if it works there.