For example, if I was writing a story, could I make up a place like, let's say, Marshmallow Hill High School and put it in Miami, even though there is no such place in Miami? I know if the plot of the story takes place in the future, then it would be fine, but what about the past or present? In a book I have read, the author made up a school and put it in her story, but is that actually okay to do? I know I probably sound like an idiot for asking this question, but and help would be much appreciated. Thank you!
(P.S. Please, do not answer this question if you aren't sure)