Need help on a calculator I'm making.

Frank,
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Having examples of calculator.

The single quotemarks should be double ("+" instead of '+' )

'+' means the char + and "+" means a string containing a +.

Now it's saying Operator '==' cannot be applied to operands of type 'string' and 'char'.
on the if statement
if (userinput == '+')

That's strange, it seems that console.read requires the user to press enter after entering the operator but it causes the console.writeline to return an empty string when the user presses any key.

This should work, I've changed the console.read to readline and made userInput a string:
static void Main(string[] args)
{
    int var1 = 0;
    int var2 = 0;
    string userInput = "";

    Console.WriteLine("Addition (+), Subtraction (-), Division (/), or Multiplication (*)");

    userInput = Console.ReadLine();

    if (userInput == "+")
    {
        Console.WriteLine("Enter The First Number You Would Like To Add: ");
        var1 = int.Parse(Console.ReadLine());

        Console.WriteLine("Enter The Second Number You Would Like To Add: ");
        var2 = int.Parse(Console.ReadLine());

        Console.WriteLine("The Answer Is: {0}", var1 + var2);
    }

    Console.ReadKey();
}

I fixed the code and it seems to work fine up until the user inputs any operator. It crashes when that happens.

If this query got resolved then please Accept the post that helped you as Answer.

So other members can easily find the answers.

The problem is that you don't put whatever the user typed in userInput so it will always remain 0.
The "Convert.ToInt32" can be changed to "Int32.Parse" or just "int.Parse".
And when displaying the result you can use "{0}" where the answer should be and add the calculaton as an extra parameter

This should work like you want it:
static void Main(string[] args)
{
    int var1 = 0;
    int var2 = 0;
    int userInput = 0;

    Console.WriteLine("Addition (+), Subtraction (-), Division (/), or Multiplicaton (*)");

    userInput = Console.Read();

    if (userInput == '+')
    {
        Console.WriteLine("Enter The First Number You Would Like To Add: ");
        var1 = int.Parse(Console.ReadLine());

        Console.WriteLine("Enter The Second Number You Would Like To Add: ");
        var2 = int.Parse(Console.ReadLine());

        Console.WriteLine("The Answer Is: {0}", var1 + var2);
    }

    Console.ReadKey();
}