According to Common Core standards, the first concepts a student should learn in math are the names of the numbers and the sequence in which to count them. From there, students are able to begin learning simple addition and subtraction.
Once students learn how to count, they can begin to group objects by quantity. In doing so, they learn to combine groups of objects, which introduces them to the concept of addition. They also learn to remove objects from groups, which introduces them to the concept of subtraction. Without first understanding the names of numbers and how to count them, however, students are unable to fully grasp the foundational concepts of addition and subtraction.