This depends on how the people became blind. People have suggested that initially after becoming blind you see ‘black’ but other people have argued against this.
If is your eyes that are damaged then your brain may still receive nerve signals from the eyes so you still may be able to have partial vision whilst if it the area in the brain that is damaged then there would be no sense of sight at all.
Hi brontesaurus! Thanks for the question 🙂 Most blind people actually can see, just not very well. Very few people can see nothing at all. A lot of people with visual impairments see shadows, grades of light, or simply have limited peripheral vision or depth perception 🙂