i am buying a pedigree puppy that has six weeks insurance what papers should i get as proof?

You should get a pedigree (either printed or handwritten) of a minimum of 3 generations, KC registration document saying the puppy's registered name, number, date of birth, the sire and dams' names and numbers and the breeder's address. You should also get the Insurance Company's cover note. Plus of course the usual diet sheet (a KC requirement).