First and foremost, viruses are not technically living organisms as they do not fulfill the criteria of living organisms (i.e they do not respire) whereas prokaryotes are. Prokaryotes have cell walls...
Viruses do not have a metabolic system of their own, they don't have a special body of their own but still are living species. they attack other cells (any other animal cell including human) and use...
viruses don't have a nucleus, and scientists have a debate on if viruses are alive because they can't reproduce on their own, also viruses are smaller than cells