I dont understand how to do integers so if you could explain with you answer that would be amazing and thank you.

1.2×10‐2
Integer is a number which is not a fraction and is whole number. Yes whole numbers are 0,1,2 and so on but integer can also be negative such as -1,-2 etc.
-3⁰= -1 which is integer
18/3(is a fraction but when solved)=6 which is integer
root under49 is 7 which is integer.
some numbers which are not integer
1.2,-3.6,1/2 etc.