You can add/subtract days/months/years from a date by using an Expression Block. The Expression Block allows you to create a variable that is equal to a logic rule. In this case, the logic rule will be X days/months/years before or after a date, like this:
In this ^ example, we're "hard coding" the value 12 but you can use a variable for that. provided the variable is a date datatype (learn more about variable datatypes).
