Can i install a windows os on my lenovo s215 laptop? It only has the free dos and it doesn't have a cdrom?

I was given a laptop by our school, Lenovo s215, but when i started it asked for a new date, a new time and asked for "C:\> " which continually appears whatever i do.So i did some research and found out that it doesn't support a window's os and only have the free DOS. So i was wondering if i can install a windows os even though it doesn't have any dvd drive on the laptop and how?

I can't see Lenovo building a laptop that didn't support a windows OS, where did you find the information that windows was not supported? Do you know the particular specs of the laptop?