Why would you?So if my Ranger took a fighting style feat instead of Druid Warrior can I cast Shillelagh from a scroll.
I am thinking not.
This. If you take Druidic Warrior and choose Shillelag as a spell, then it becomes a ranger spell for you, but since you have it as a prepared spell, you don't need it on a scroll. If you pick a different cantrip or you don't choose Druidic Warrior, then it is not a ranger spell for you and you can't read it from a scroll.Druidic Warrior does specifically say that if you have that Feat, the chosen cantrips "count as ranger spells for you" (emphasis mine). This implies that if you don't have the Feat, they are not Ranger spells, hence a Ranger couldn't ordinarily cast them from a scroll.