Flour and salt are the two critical quantities in bread making. We covered flour; salt is much easier.
Salt adds flavour, but more importantly [[Fermentation_Rate?|it slows down the fermentation]] - yeast doesn’t like salt at all.
The usual amount of salt is about ¾tsp of salt per cup of flour. Much more or less and the dough will be slow or fast to rise. Butter has a tiny amount of salt in it so if you added salted butter, you can decrease the salt added by maybe ⅛tsp per cup of flour.