Creating a function to read line in C#

I have a text file as follows:

NPSER   NASER   NQSER
10  5   3
JPNM    EPNS    RNPS
12  10  11
ACBE    MNEF    QPNS
25  11  78 

This is a simplified data from my long data. I want to automatically find the values of NPSER, NASER, NQSER and so forth.

So far my code is as follows:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace read_file
{
    class Program
    {
        static void Main(string[] args)
        {
            TextReader namefile = new StreamReader(@"E:\Code in C Sharp\read-file\read-file\test.txt");
            string line = namefile.ReadLine();
            Console.WriteLine(line);
            Console.ReadLine();

            ////Read second line
            string line1 = namefile.ReadLine();
            Console.WriteLine(line1);
            Console.ReadLine();
        }

        static public string[] Returnval(string line)
        {
            var Returnval = line.Split('\t');
            return Returnval;
        }
    }   
} 

I have created a function Returnval which splits the string which are tab separated. I want to modify this function which would automatically take new line as input and then I should be able to use the function like this:

Returnval(NPSER, NASER, NQSER)  

I tried to add a new line to Returnval function which is as follows:

string line = namefile.Readline(); 

I got an error saying namefile is not in context.

Any suggestions are highly appreciated.

---

Regards, Jdbaba