Did cookies exist in Medieval Times?

Answer 1

Yes, many medieval people had cookies. Cookies, pretty much as we would recognize them, were developed in Persia. Their use spread with the spread of Islam, and they were introduced by Muslims who invaded Spain in 711. From that point they spread through Europe, and were common throughout European society by the 14th century.

Answer 2

as far as we know, no. Most cookies require baking powder or baking soda for leavening, both of which were invented after the mid-18th century. A similar chemical, ammonium bicarbonate (also known as sal volatile or salt of hartshorn), existed in the late middle-ages but wasn't used in baking until the 17th century.