People with schizophrenia see what is not there and believe it to be real, people with derealization see what is there but don't believe it to be real- this is me, I see everything and it always looks like a dream.
Derealization is just the feeling or sensation that what is happening to you or around you is not real, like a dream. People with anxiety get this all the time. Schizophrenia is seeing or hearing things that are not there. They are two different things.