Question

Why 0/0 is not defined it can be from
-infinity to + infinity

Answer 1

because it can have any value in the number system not necessarily infinity but any number and so it does not gives any definite value

Answer 2

According to the definition of a rational number it is a number that can be expressed in the form of p/q, where p and q are co-prime and q  is not equal to zero.

But, in the number 0/0 if we consider the numerator as p and denominator as q then it is contradicting to the definition of a rational number given above. Hence, it is an irrational number and that's why it is not defined.