Plotting Durations

Due to changes on the request - I thought it was best to close this post - so I marked it Solved.

I am trying to come up with the best method in plotting duration on excel for various projects. I have a start and finish date and have calculated the duration by number of dates. But I do not know how to get that information on automatically to populate on the calendar accordingly. I have attached my spreadsheet of the look I am looking for and what I would like for it to do. Any advise or help on the best method for this.