One photo out of focus is a mistake, ten photos out of focus are an experimentation, one hundred photos out of focus are a style.
What is OOF? OOF means out of focus in photography.
It is interesting, I can give an assignment.
Switch your camera/lens to manual focus if you like to do so and make photos without proper focusing. The rule is, not proper focusing. Try to be creative and make the best photos you can do that way.
What is forbidden to do what your camera’s autofocus would do, to make a “normal” picture.
Change apertures, try to find light sources in the background. You can make landscapes, pictures about people, anything you like to. The goal is to make an articstic picture using OOF technique.
With bigger apertures from closer distances, you can blur the background more, than with smaller apertures or longer distances.
Check what is your lens closest focusing distance, and try to use around that as well.