using System;

using System.Collections.Generic;

using System.Linq;

using System.Linq.Expressions;

​

public class Item

{

    public string PARTICULARS { get; set; }

    public string CATAGORY { get; set; }

    public string DETAIL { get; set; }

}

​

public class Program

{

    public static void Main(string[] args)

    {

        var A = new List<string> { "EXWORK", "CENTAGES", "PREMIUM" };

        var B = new List<Item>

        {

            new() { PARTICULARS = "EXWORK", CATAGORY = "ERECTION", DETAIL = "ABC" },

            new() { PARTICULARS = "CENTAGES", CATAGORY = "ERECTION", DETAIL = "ABC" },

            new() { PARTICULARS = "PREMIUM", CATAGORY = "SUPPLY", DETAIL = "ABC" }

        };

        var value = A.Except(

            B.Where(b => b.CATAGORY == "SUPPLY")

                .Select(b => b.PARTICULARS));

        Console.WriteLine(string.Join(Environment.NewLine, value));

    }

}

​