Of is used when talking about something that belongs to an object -piece of paper (piece belongs to the paper) -part of a group (belongs to the group) or i could say that im thinking of (about) something. The word of is an extremely hard concept to explain but i tried my best to help you. From is used when talking about something that was given or location. -I got this picture from my best friend -he is from spain -This gift was from Karen -where did you come from? I hope I helped if even a little bit.