C# Online Compiler | .NET Fiddle

using System;
using System.Collections.Generic;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		var db = FakeDbContext.Seed();

		// write the output
		DumpTable(db.Hato, "All HATO Records");
		
		DateTime startDate = new DateTime(2021,05,21);
		DateTime endDate = new DateTime(2021,05,24);
		
		// verify the date filter results
		DumpTable(db.Hato.Where(L => L.HatoRecDate >= startDate && L.HatoRecDate <= endDate), String.Format("HATO Between [{0:dd.MM.yyyy} - {1:dd.MM.yyyy}]", startDate, endDate));
		
		var qLocation = (from L in db.Hato
                         where L.HatoRecDate >= startDate && L.HatoRecDate <= endDate
                         group L by L.HatoLocation into g
                         select new { HatoLocation = g.Key, count = g.Count() })
                        .OrderByDescending(o => o.count).ToList();

		// write the results to the output
		DumpTable(qLocation, "qLocation Grouping Results");
		
        var l = qLocation[0].HatoLocation;
        var c = qLocation[0].count;
		
		Console.WriteLine("qLocation[0].HatoLocation: {0}", l);
		Console.WriteLine("qLocation[0].count:        {0}", c);
	}
	
	public class FakeDbContext
	{
		public static FakeDbContext Seed()
		{
			var db = new FakeDbContext();
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,21), HatoLocation = "A" });
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,21), HatoLocation = "A" });
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,23), HatoLocation = "B" });
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,24), HatoLocation = "A" });
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,24), HatoLocation = "B" });
			
			// Add one entry either side of the date to prove the filter condition
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,20), HatoLocation = "A" });
			db.Hato.Add(new Hato { HatoRecDate = new DateTime(2021,05,25), HatoLocation = "B" });
			return db;
		}
		public ICollection<Hato> Hato = new HashSet<Hato>();
	}
	
	public class Hato
	{
		public DateTime HatoRecDate { get;set; }
		public string HatoLocation { get;set; }
	}
	
	/// <summary>.Net Fiddle Helper to dump the contents of an IEnumerable out to the Console Output so we can cut'n'paste a table into Stack Overflow!</summary>
	public static void DumpTable<T>(IEnumerable<T> table, string header = null)
	{
		if(!String.IsNullOrWhiteSpace(header))
			Console.WriteLine("// {0}", header);
		
		var columns = typeof(T).GetProperties();
		Console.WriteLine("|{0}|", String.Join("|", columns.Select(c => c.Name)));
		Console.WriteLine("|{0}|", String.Join("|", columns.Select(c => new String('-', c.Name.Length))));
		
		foreach (T record in table)
		{
			Console.Write("|");
			foreach (var c in columns)
			{
				Console.Write("{0}|", c.GetValue(record, null));
			}
			Console.WriteLine();
		}
		Console.WriteLine();
	}
}

 
using System;
using System.Collections.Generic;
using System.Linq;
                    
public class Program
{
    public static void Main()
    {
        var db = FakeDbContext.Seed();
​
        // write the output
        DumpTable(db.Hato, "All HATO Records");
        
        DateTime startDate = new DateTime(2021,05,21);
        DateTime endDate = new DateTime(2021,05,24);
        
        // verify the date filter results
        DumpTable(db.Hato.Where(L => L.HatoRecDate >= startDate && L.HatoRecDate <= endDate), String.Format("HATO Between [{0:dd.MM.yyyy} - {1:dd.MM.yyyy}]", startDate, endDate));
        
        var qLocation = (from L in db.Hato
                         where L.HatoRecDate >= startDate && L.HatoRecDate <= endDate
                         group L by L.HatoLocation into g
                         select new { HatoLocation = g.Key, count = g.Count() })
                        .OrderByDescending(o => o.count).ToList();

Cached Result

// All HATO Records
|HatoRecDate|HatoLocation|
|-----------|------------|
|5/21/2021 12:00:00 AM|A|
|5/21/2021 12:00:00 AM|A|
|5/23/2021 12:00:00 AM|B|
|5/24/2021 12:00:00 AM|A|
|5/24/2021 12:00:00 AM|B|
|5/20/2021 12:00:00 AM|A|
|5/25/2021 12:00:00 AM|B|

// HATO Between [21.05.2021 - 24.05.2021]
|HatoRecDate|HatoLocation|
|-----------|------------|
|5/21/2021 12:00:00 AM|A|
|5/21/2021 12:00:00 AM|A|
|5/23/2021 12:00:00 AM|B|
|5/24/2021 12:00:00 AM|A|
|5/24/2021 12:00:00 AM|B|

// qLocation Grouping Results
|HatoLocation|count|
|------------|-----|
|A|3|
|B|2|

qLocation[0].HatoLocation: A
qLocation[0].count: 3