It seems that there is no form of defining the range of variables as you said, only the types of variables are defined as ~ integer -32 32,768 to 32,767, long integer -2,147,483,648 to 2,147,483,647 and so on.

If you want to limit the range of variables, you can only write your own code restrictions.

If a>= 100, then a= 100. In this way, A can never exceed 100.