V-IV-I Transitions Improvising Study 4

Dave, It seems like every time I move on to the next lesson, I always run into a mountain.. Some things come very natural to somepeople. I AM NOT ONE OF THOSE PEOPLE, even though I try hard, IT seems lile I alwaYS GET LOST. So this is a question that might help clear things up for me. If I was playing my F HARP, for example, The notes for my I chord would be C E G Bb ..... The notes for my IV chord would be F A C Eb, and my V chord the notes I want to use are G,Bb,D , and F. I think Im either getting close to undertanding this or I will start from scratch for al the lessons for imprivising study 4 i dont want to move on until I get a handle on this. Sorry for being such a slow studen, just want to make sure I know what Im doing.