We do not consider zero to be a positive or negative number. For each positive integer, there is a negative integer, and these integers are called opposites. If an integer is greater than zero, we say that its sign is positive. If an integer is less than zero, we say that its sign is negative. If instead, I take 8 steps backwards , we might consider this a -8.
Temperature is another way negative numbers are used.
The number of units a number is from zero on the number line. When adding integers of the same sign, we add their absolute values, and give the result the same sign. The absolute values of 8 and -3 are 8 and 3. The absolute values of 8 and -17 are 8 and 17. The absolute values of -22 and 11 are 22 and 11.