If you're using the recipe calculator, you're already in the "edit" part and "recipe tools" drop down is at the top right part of the page. It's where you get to the "scale", "share" and other functions.
OK i found it. Sorry for the dumbness.
I changed the American Pale Ale Single Hop - Cascade recipe from 21lts to 10lts and it adjusted the boil amount. With the fermentables, hops and yeast do you need to enter the original quantities for 21lts and the edit tool will automatically adjust the quantities needed for a smaller batch?
So when i adjust the batch size it will change the hops etc if needed. So its saying now same amount of hops for a 21lt and 10lt batch. With the fermentables it says 50% bill, so does that mean half the fermentable but no change to the hops.