public static void Main()
Console.WriteLine("Enter a number: ");
var userInput = Console.ReadLine();
var isNumeric = int.TryParse(userInput,out n);
Console.WriteLine("Your selected course is IT 145");
Console.WriteLine("Your selected course is IT 200");
Console.WriteLine("Your selected course is IT 201");
Console.WriteLine("Your selected course is IT 270");
Console.WriteLine("Your selected course is IT 315");
Console.WriteLine("Your selected course is IT 328");
Console.WriteLine("Your selected course is IT 330");
Console.WriteLine("Please enter a number 1-7");
Console.WriteLine("Please input a number");