You can try scanning negatives the same way you scan prints, but the results may not be great. Scanners that are designed to scan negatives usually have some way to put light behind the negative to make sure it scans with enough contrast. They often also come with special holders for negatives. I don't know if your model was specifically meant to do negatives, but you can't hurt anything by trying.
After you scan a negative you need to convert it to a positive. The scanner may have come with software that can do this. If not, IrfanView
is a free program that can do that as well as much more. It's a great general-purpose image viewer, so it's worth downloading in any case.