using static System.Console;

using System.Collections.Generic;

using System.Linq;

​

public class Program {

    public static void Main() {

        var lista = new List<string> { "1,Joao",

            "2,Maria",

            "3,José1" };

        var nome = lista.Select(x => x.Split(',')).SingleOrDefault(a => a[1].Contains("1"));

        var id = lista.Select(x => x.Split(',')).SingleOrDefault(a => a[0].Contains("1"));

        WriteLine(nome[1]);

        WriteLine(id[1]);

    }

}