Reducing entries when calling a function

Good day!

There is a code, please tell me what technology of the C # language should I use and how it is called, in order to implement the process of assigning the enum variable when calling the Summ() function of the Summ() class

 enum AnyEnum { FIRST_VALUE, SECOND_VALUE } internal class AnyClass { int a = 0; internal void Summ(AnyEnum enum) { if(enum == AnyEnum.FIRST_VALUE) a = 5; else if(enum == AnyEnum.SECOND_VALUE) a = 10; } } internal class MainClass { int f = 0; public MainClass(int f) { this.f = f; AnyEnum enum = AnyEnum.FIRST_VALUE; if(this.f > 5) enum = AnyEnum.SECOND_VALUE; AnyClass anyClass = new AnyClass(); anyClass.Summ(enum); } }