https://m.youtube.com/channel/UCbAea8pF8VufHtNr9mQv1Iw You can find aircraft specifications including the brand, type, and diameter of prop for any aircraft online or in a library.
Using typical scales such as 1/12” or 1/18” or 1/32” and convert the real world prop dimensions to the required scale. ie: in 1/12” scale a 9’ diameter prop would have a 9” diameter on your model because 1” = 1’ In that scale
The link is to my youtube channel Heywood Planes and there are a few vids there that show how I made the prop for my Flyline Models 1/12” scale Stearman Cloudboy.