How can I make sure user input must be the same input I need from my array

I am a beginner. I have this problem I am not sure if I will be able to explain it adequately but let’s see:

I have an array called userid and another array called username. I want the user to give me his/her id after that I wish that the name user will type has to be the same array number from the username array
for example if the user types 5 then his/her name must be "f" otherwise user can’t go any further.

I don’t know what to type in if statement?

class Program
{
    static void Main(string[] args)
    {
        string[] userid = {"0" , "1" , "2" , "3" , "4" , "5"};

        string[] username = { "a" , "b" , "c" , "d" , "e" , "f"};

        Console.Write("please type user id: \t");

        string useridreply= Console.ReadLine();

        Console.Write("please type user name: \t");

        string usernamereply = Console.ReadLine();

        if (usernamereply = username[useridreply])
        {
        }
    } 
}

>Solution :

in your if-condition you forgot to add one more “=”.
In C# the syntax for comparing two values is “==”.

So your if-condition would look like:

if (usernamereply == username[useridreply])

Here is another helpful link to the microsoft documentation for the comparison operators: https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/operators/comparison-operators