How to use multiple methods in C#?

Or in short, I can't get it.

I have been looking up and studying things in C# for the past couple of days, but there is one things I can't figure out: How I can use multiple methods and call them back to main (). (I really hope I am phrasing this right.) So I am trying to do a simple project to help me with other projects, but even the simple project isn't doing much help.

Basically this: I am making a console program in VB that can take 2 integers from the user in main (), then it has to call the sum, product, difference, and so on from a different method back into main ().

The code I currently have looks like this:

 Spoiler

Code:

using System;

namespace _3B1
{
    class Program
    {
        static void Main()
        {
            int x;
            int y;
            

            string inputValue;

            Console.WriteLine("Enter the first number: ");
            inputValue = Console.ReadLine();
            x = int.Parse(inputValue);
            Console.WriteLine("Please enter the second number: ");
            inputValue = Console.ReadLine();
            y = int.Parse(inputValue);
        }

        public static int formulas()
        {
            sum = x + y;
        }
    }
}

I think I have the top part right, but I keep messing up with the creation of a new method. I can do this all when it's in one method, but for the sake of a class, I have to know how to use and create new methods.
I haven't finished it yet, as I am still having trouble getting the sum of the two to work right.
If anyone can help me out, I would really appreciate any advice or tips I can get on this. I would like to settle down and learn this once and for all.