Basic console calculator with four operations
Compactness


use a switch statement rather than verbose if-elseif-.. statements
get rid of redundant blank lines




Readability

Avoid escaping characters.


Console.WriteLine("Type \"+\" for addition");
Console.WriteLine("Type \"-\" for subtraction");
Console.WriteLine("Type \"*\" for multiplication");
Console.WriteLine("Type \"/\" for division");



You could go with..

Console.WriteLine("Type '+' for addition");
Console.WriteLine("Type '-' for subtraction");
Console.WriteLine("Type '*' for multiplication");
Console.WriteLine("Type '/' for division");


Or..

Console.WriteLine(@"Type ""+"" for addition");
Console.WriteLine(@"Type ""-"" for subtraction");
Console.WriteLine(@"Type ""*"" for multiplication");
Console.WriteLine(@"Type ""/"" for division");




User Experience

If you ever wish to design end-user interfaces, you have to work on your lingo.  

You're off to a good start:


Console.WriteLine("Hi! What is your name?");



You slip up slightly next (forgot a question mark):


Console.WriteLine(name + " What do you wanna do");



But then you start pressuring the end-user. You expect a number, not in a moment, but Now! And you are not asking, you are demanding.


Console.Write("Now, Give me number one: ");



Also, one time with a comma and capital after it, and one time the other way around:


Console.Write("Now give me number two: ");



The user may also expect this application to crash on:


double num1 = Convert.ToDouble(Console.ReadLine());
double num2 = Convert.ToDouble(Console.ReadLine());
Console.WriteLine(num1 / num2); // when num2 is 0
Any other overflow


And nothing happens when an unknown operator is provided by the user.

The user is not able to verify the results, since the application immediately terminates after the calculation is evaluated.