is this right that we have to switch the numbers in prenthessis in commutative and in associative we just have

Answer 1

Examples of commutative = "switching":
a + b = b + a
(a + b) + c = c + (a + b)
(a + b) + c = (b + a) + c

Example of associative = "regrouping":
(a + b) + c = a + (b + c)

Answer 2

yes
you are correct